A shoulder bag will do.
Although freshmen and even sophomores have backpacks, juniors don't have them.
Of course, the premise is that if it is only a college class.
If you are taking the postgraduate entrance examination and don't have a fixed seat, you still have to carry a backpack because there will be a lot of things.
How much you take in a college course depends on what the course is and whether you like it or not.
Things can be so few that you can go home empty-handed
At most, it is a textbook, a notebook, some pens, and sometimes you need to bring a USB flash drive to hand in your homework.
There are not many things.
If it's a girl, of course it's a shoulder bag. Beautiful, feminine, enough.
For boys, the boys in my class are usually messenger bags or books and pens in their hands.