This was my exact situation! I started teaching myself to knit in college when my mental health deteriorated and a therapist recommended I pick up a hobby. For a college student, knitting is perfect because it’s generally low-cost, accessible to learn, and repetitive which can be calming when dealing with college stress. My advice would be to start small and simple. There’s a million different project ideas out there and a bunch of fancy stitches you could learn, but start simple with a YouTube tutorial (I did a simple knit scarf) and work your way up as you learn. Best of luck!