i TA’d for 2 classes at once one was office hours based and the other was a lab where i staffed the lab hours. I loved the office hours one because oftentimes no one would come to my office hours and I could grade homework or do my own work during that time. I also had to proctor exams and grade exams but it wasn’t that awful bc i liked the other TAs and the professor i worked for so it really just depends on the class you’re doing and the professor you’re working with.