@AmiraRida22 ...
Canvas is a LMS (Learning Management System) that many schools all over the world use to host their online/hybrid classes. In looking at UCLA's website, I *think* that they use Canvas as their LMS? But, I'm not 100% sure.
Unfortunately, I am not employed by UCLA, so I cannot comment on where exactly your coursework would be located. I assume it would be in a course within your LMS. This is ultimately a question that you're going to need to ask someone at UCLA. You might try contacting UCLA's Online Learning / eLearning / Distance Education department to see if they can help you out. Or, you might try reaching out to their Registration department, and they could at least point you in the right direction. Again, you could try contacting your instructor (if you know who that is), too.
Hopefully you'll be able to get in contact with someone soon to get this all sorted out. Good luck to you!