College Football has a few different rules than the NFL, one of the bigger ones was that the clock stops on 1st downs. Games were getting longer and longer and the NCAA decided to make a clock change this season. This season the clock stops on 1st downs only with 2 minutes left in each half.
Per Tej Seth on X formerly from PFF:
# of plays difference between last season and Week 0 and 1
2022: •plays per game: 131 •drives per game: 24.0 •plays per drive: 5.50 2023: •plays per game: 117 •drives per game: 21.