good luck. your choice of supermarket work sounds like a good idea. go for it.
when i was young [decades back], my entry-level jobs were fast-food, professional picketer for unions, phone banks [solicitation], janitorial work, the military. nowadays, [largely due to outsourcing] outside of produce-picking, there are relatively few non-military entry-level jobs as commonly understood decades before the gradually insidious inflation of educational requirements became the elephant in the room. "mcjobs" such as floor-work at walmart or fast food will gradually become obsolete as robotic technology replaces these one by one. i would not count on your supermarket job being there in a few years. so jump on it now before technological progress usurps your job. the powers that be have mandated that everybody and their brother go into hock and burn the midnight oil for years in college, just to get that precious piece of paper in order to get the lions' share of the good-paying jobs left in today's economy.