That's what I do. I don't have a job during the school year (I do work during the summer). I have just enough energy and executive function to manage all the work for 4 classes (a full course load at my school) while eating, sleeping, doing online stuff like this sometimes, and seeing friends occasionally. If I tried to do anything else, be it a 5th class, a club, or a job, I wouldn't be able to manage. Honestly, I'm kind of jealous of my friends who are in several clubs while taking demanding classes. They're having all sorts of fun and enriching experiences, while still getting something out of their classes, so they'll truthfully be able to look back at college and say, "this was the best time of my life." I'm missing out on most of the fun parts of college, so the "best time of my life" will probably end up being something else.
At my school, students put on a lot of concerts and plays, volunteer at all sorts of interesting places, and take part in a lot of activities. If it's possible for you to try some of these things while still focusing on your schoolwork, it might be worthwhile. These sorts of things, NOT drinking and partying, are the real "college life," IMO.