The seasons of the year

In the middle of the creation account, God created a distinction between a day, a season and a year. This indicates that they are different lengths of time.
If we want the days of creation as a long period of time then what is a season or what is a year?
The whole verse fails to have any meaning if a day is not a literal day.
Does a season become an extra long indefinite period of time? And how long of an indefinite period of time is a year? When we add man's fallible changing ideas called evolution into the Bible then the Bible makes no senses.
Why change the clear meaning of the Bible for an idea called evolution. The changing model depending of the current understanding of the scientific evidence.

Genesis 1:14

 And God said, “Let there be lights in the vault of the sky to separate the day from the night, and let them serve as signs to mark sacred times, and days and years,