If you have not read Stories Versus Truth, you may want to read that before reading this.

The reason Christ-followers believe what they believe is not based on physical evidence or human argument, although the observable physical evidence supports God's Truth without the mental gymnastics that the Atheists and Evolutionists find themselves tangled in.  The reason we believe is based in the power of God. 

Faith comes by hearing and hearing by the word (utterance) of God. God speaks. God speaks to every person. Whoever will listen receives the faith that is of God.  This is a supernatural belief that is not human-generated.  It is a gift.  That faith is the belief that what God has said is true.  Before a person is born again, that person will likely have already heard God's voice for some time.  No one can come to Christ unless the Father draws him or her.  And a person is born again the moment that he or she hears God's voice and receives faith to believe in Jesus as Savior from sin. So, God speaks to us, often, through the Bible.  It is God who speaks and says that the Bible is the Word of God without error.  When we hear His voice, then His faith comes, the supernatural belief that the Bible is the Word of God without error.

(some caveats about hearing God's Voice)

Chart explaining how time from the Creation to the present can be calculated using Scripture?

Here is what God says through the Bible.

Exodus 20:11 "For in six days the LORD made the heavens and the earth, the sea, and all that is in them, but he rested on the seventh day."

Genesis 1:1-31 In the beginning God created the heaven and the Earth. and the Earth [was] without form, and void; and darkness was on the face of the deep. And the Spirit of God hovered over the face of the waters.  God said, "Let there be light." and there was light, and God saw the light, that it was good: and God divided the light from the darkness, and God called the light Day, and the darkness He called Night, [and that was the] evening and the morning [of the] first day, God said, "Let there be an expanse in the midst of the waters, and let it divide the waters from the waters." and God made the expanse, and divided the waters which were under the expanse from the waters which were above the expanse correctly,  and God called the expanse, Heaven, [and that was the] evening and the morning [of the] second day. God said, "Let the waters under the heaven be gathered together to one place, and let the dry land appear." and God called the dry land Earth; and the gathering together of the waters He called Seas: and God saw that it was good, and God said, Let the Earth bring forth grass, the herb yielding seed, and the fruit tree yielding fruit after his kind, whose seed is in itself, upon the Earth: and it was so, and the Earth brought forth grass, and herb yielding seed after its kind, and the tree yielding fruit, whose seed was in itself, after his kind: and God saw that it was good,  [and that was the] evening and the morning [of the] third day. God said, "Let there be lights in the expanse of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years: and let them be for lights in the expanse of the heaven to give light upon the Earth." and God made two great lights; the greater light to rule the day, and the lesser light to rule the night: He made the stars also, and God set them in the expanse of the heaven to give light upon the Earth, and to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good, [and that was the] evening and the morning [of the] fourth day. God said, "Let the waters bring forth abundantly the moving creature that has life, and fowl that may fly above the Earth in the open expanse of heaven, and God created great whales, and every living creature that moves, which the waters brought forth abundantly, after their kind, and every winged fowl after its kind." and God saw that it was good, and God blessed them, saying, Be fruitful, and multiply, and fill the waters in the seas, and let fowl multiply in the Earth, [and that was the] evening and the morning [of the] fifth day. God said, "Let the Earth bring forth the living creature after its kind, cattle, and creeping thing, and beast of the Earth after its kind." and God made the beast of the Earth after its kind, and cattle after their kind, and everything that creeps upon the Earth after its kind: and God saw that it was good. God said, "Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the Earth, and over every creeping thing that creeps upon the Earth." so God created man in His own image, in the image of God He created him; male and female He created them, and God blessed them, and God said to them, Be fruitful, and multiply, and fill the Earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moves upon the Earth. God said, "See, I have given you every herb bearing seed, which is upon the face of all the Earth, and every tree, in the which is the fruit of a tree yielding seed; to you it shall be for meat, and to every beast of the Earth, and to every fowl of the air, and to everything that creeps upon the Earth, in which there is life, I have given every green herb for meat." God saw everything that He had made, and, it was very good, [and that was the] the evening and the morning [of the] sixth day.

Matthew 1:1-17 The book of the generation of Jesus Christ, the son of David, the son of Abraham. Abraham fathered Isaac; and Isaac fathered Jacob; and Jacob fathered Judas and his brothers;  And Judas fathered Phares and Zara of Thamar; and Phares fathered Esrom; and Esrom fathered Aram;  And Aram fathered Aminadab; and Aminadab fathered Naasson; and Naasson fathered Salmon;  And Salmon fathered Booz of Rachab; and Booz fathered Obed of Ruth; and Obed fathered Jesse;  And Jesse fathered David the king; and David the king fathered Solomon of her who had been the wife of Urias;  And Solomon fathered Roboam; and Roboam fathered Abia; and Abia fathered Asa;  And Asa fathered Josaphat; and Josaphat fathered Joram; and Joram fathered Ozias;  And Ozias fathered Joatham; and Joatham fathered Achaz; and Achaz fathered Ezekias;  And Ezekias fathered Manasses; and Manasses fathered Amon; and Amon fathered Josias;  And Josias fathered Jechonias and his brothers, about the time they were carried away to Babylon:  And after they were brought to Babylon, Jechonias fathered Salathiel; and Salathiel fathered Zorobabel;  And Zorobabel fathered Abiud; and Abiud fathered Eliakim; and Eliakim fathered Azor;  And Azor fathered Sadoc; and Sadoc fathered Achim; and Achim fathered Eliud;  And Eliud fathered Eleazar; and Eleazar fathered Matthan; and Matthan fathered Jacob;  And Jacob fathered Joseph the husband of Mary, of whom was born Jesus, who is called Christ.  So all the generations from Abraham to David are fourteen generations; and from David until the carrying away into Babylon are fourteen generations; and from the carrying away into Babylon to Christ are fourteen generations.

(Note: when calculated, this genealogy comes out to about 6,000 years.)

 Mark 10:6-8   But at the beginning of creation God "made them male and female. ... For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh." So they are no longer two, but one.

(Note: Genesis is written as real history and Jesus spoke of it as real history.)

Romans 5:12  Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all men, because all sinned

(Note: there was no death before one man, Adam, sinned.)