There are various beliefs as to the age of the earth and the universe many of which range from the absurd to pure speculation.
Young earth creationist, generally fundamentalist Christians believe in a literal interpretation of the Genesis account that the creative days of Genesis were six literal (24-hour) days, which occurred 6,000 years ago.
However we believe we are not to suppose those days were literal 24 hour days, but rather each consisting of the same length as the last creative day. As you recall Adam was created at the very end of the sixth day and the beginning of the seventh day was just opening up. Now since the Lord gave us a pattern in the seven days of a week, the last day being the Sabbath we merely need to transfer this same principle to the creative days. A day with the Lord is as a thousand years, thus the first six days from Adam’s creation brings us to 6000 years with the last, the seventh 1000 year day, the millennial being the Sabbath or the Day of the Lord.
Now as order is Heavens first law it is only logical to assume that each of the preceding days were of equal length that is 7000 years each or 7000 X 7000 = 49,000 years since the beginning of creation (as in accordance with the Jubilee cycles). We are about to reach the Fiftieth or Grand Jubilee, the restoration of all things.
The narrative given in the Genesis account is the record of creation not from the beginning of the creation of the universe (which is untold billions of years old), but from the point of preparing the earth for the arrival of man. Note in the 2 verse of Genesis, “Now the earth was formless and empty…” The key word here is “was”, the earth already existed, but as yet was formless and void (of life). We can accept what scientist suggest as the age of the earth being 4.5 billion years old, but creation itself is just a little over 49,000 years old and man a little over 6000 years.
My thoughts