Where is there an account from history that allows you to fully understand and explain the number of years that the Earth has existed? The only place we can know is the Bible itself. If you don't believe in the Bible as a divine writing or an instruction from God, then consider it from a historical perspective, because the Bible has been shown to be very accurate regarding historical evidence.
There are actually a couple of ways to determine the age of our earth using historical means in the Bible, and they both result in the same time period. One is through historical events and the other is through documented genealogy. You can know more about Biblical and world history through online sources.
The Biblical age of the Earth is only about 6,000 years old. According to a historically documented account, humanity did not evolve 4 million years ago on an Earth that is 4.5 billion years old. Jesus Christ, the Incarnate Creator, said that he made mankind male and female in the beginning, in Mark 10: 6, and that's when the heavens and the earth were commanded to exist, as read in Genesis 1: 1.
The Bible contains extensive genealogies, these records play a vital role in biblical literature, which is clear from the amount of space devoted to them in God's Word. In addition, they also provide tremendous protection of the text through the message they convey. Although genealogies and chronologies serve various functions in the literature of the Scriptures, one of their primary purposes is to show the historical connection of great men to the unfolding of Jehovah's redemptive plan. Therefore, these lists form a connecting link from the earliest days of mankind to the completion of God's system of salvation.