Can I retake all of my classes?

Hi, after 2 years of attending I decided to drop out of community college about two quarters ago and I’m planning on going back this upcoming Fall. The problem is, I didn’t do as well as I wanted and I pretty much forgot what I learned in my prerequisite classes. I’m worrying that if I go into classes like Calculus it would be very difficult for me since I forgot what I learned in the prerequisite classes. I understand that I’m unable to reset my transcript but would I be able to just re take all of the classes at that community college even though I passed them? I don’t mind if it prolongs my time into transferring. What if I started attending a new community college? Thanks.

I’m attending community college in California if that helps

In two or three quarters you haven’t forgotten everything. You can do some review now with your old textbooks and at websites like khanacademy.org and patrickjmt.com. When you start classes again, use the tutoring center on campus to stay on top of your classwork.