The internet is the fast food of socialising. While it might be quick and easy, the quality is terrible. You’ll make real life long friends just being in the same room as someone regularly and chatting face to face.
IIRC, it's harder than high school to make friends at a university. It's bigger and more anonymous, and outside of student housing there's less free time where students are forced together.
My high school class wasn't too much larger than Dunbar's number (300), and you were getting mixed up with the same kids for 6 hours straight for 6 years.
My university wasn't even that large, and I think there were ~>3,000 kids in my year and plenty enough in my major that it wasn't uncommon (without deliberate effort) to have zero overlap from semester to semester.
If you're eating alone at your desk, you are signaling that you wish to be left alone.