Tell her you’re sorry for cheating but that you just didn’t understand what she was teaching. And then tell her that you were embarrassed to ask for help.
Try a compromise. I'm not going to assume you cheated just out of pure laziness. This school year was kinda hard. Online learning wasn't very effective. I'm sure the only reason you cheated was because you didn't understand the material and it can be hard to ask for help online. I would say be honest with the teacher and apologize and tell her that you didn't mean to cheat and that you were desperate. I'm sure they'll understand due to the climate of this school year. Try asking if you could work with them after class when everyone leaves.
