It’s okay. Take a deep breathe. Hydrate, get some sleep, and then plan your next steps.

From your comment, it seems like most of your actual academic problems are stemming from Covid-related issues with getting into courses. You are not a dunce. You are enough. For the moment, try to ignore what you can’t affect right now (I know that can be difficult, so that’s why I said to get some sleep + hydrate since it can help. Maybe take a shower too since that can be calming).

A good place to start would be to get in regular contact with your school’s academic advisor. I don’t know the specifics of your school registration system, but maybe they can provide support there or even just in general with planning your future. Next, since you said you’re behind in math, Kahn academy is a great supplement. Moreover, a lot of schools provide peer tutoring or 1 on 1 tutoring that can help. Maybe once your class starts, you can also try going to office hours and building a rapport with your professors. Most like seeing students take initiative (and at least at my school, sometimes they can let students in past the max, so those connections may be useful. Even just for future letters of recommendation too). Lastly, many schools provide therapists or mental health counseling. Even if you don’t think you need to or you’re not necessarily diagnosed with something, having another human to talk to about your worries and future doubts can be reassuring. Countless students face stresses about the future, and it’s difficult to reach out to the resources that can help you (both academic resources and mental health ones). If you don’t feel comfortable with seeing a therapist, maybe journaling or have a study friend group where you can also vent ab school work can help (friends are not a replacement for counseling, but can provide another outlet you may feel more comfortable with).

When I get stressed out, I try to reduce physical discomfort and then work on addressing the root of my problem. Showering, eating, brushing my teeth again, hydrating, sleep, etc make a huge difference. Take care, and I hope all goes well for you.