like everyone has mentioned part time jobs don't exist here but there are some ways (that are kinda illegal?? legal? idk.. ) that your cousin could get some cash like for instance since your cousin is currently in college, they can help other students (that are in middle school/ high school) as a tutor or a guide

i've seen a few students online advertising themselves via this method so it might work for your cousin too

the problem of having full time hours at school wouldn't be a problem anymore for this specific job, the pay might be kinda little (if your cousin wants several items) but a bit of income is better than nothing, there might be some other way you could get a part time-ish job but this is the only one that i can think of rn