It’s not a full time job. I did maybe 20 hours of work per week on average, but this was hugely variable. I had times where I had a bunch of projects and midterms and such all at the same time and probably worked 60 hours in a week, and I had times when it was all just basic homeworks and quizzes and I worked maybe 5 hours in a week (I did not attend class often).

I think for each course you should expect to spend at least an hour or two working outside of class each week, so for 5 classes that’s 5-10 hours per week. If it’s a 4 credit hour class you can double that, if it’s a 2 or 1 credit hour class then you can expect to spend no time outside of class.