IMO, preschool should involve lots of group activities and dramatic play to encourage creativity and build social skills. Every child is different though, and it’s OK for kids to explore their own interests too. On some days at preschool, my daughter would be “running an ice cream shop” with other kids during dramatic play. On other days, she’d spend time by herself completely focused on doing puzzles.

Good luck to you and your son (whether in preschool or kindergarten this year)!