First day of school tips?

My son starts school tomorrow and I’m so nervous. He did go to daycqre before, but not for the last 6 months. So he has some experience but he has a hard time with new things. I just know hes going to cling onto me and not go inside and cry🥲

Ive taken him to see the school and kind of get familiar. We talk about school everyday. Do most kids freak out at first and then get adjusted to school? Hes my first child.