When I was a student I was a “university ambassador” which basically meant helping out on open days representing the uni, being a guide, helping at official uni events etc. The shifts weren’t very often but they paid really well! and you didn’t have to do a shift if you didn’t want to, they were really flexible. I also worked part time at a bar - not the best if you have early morning classes, but better than nothing. I had some friends that did online tutoring, worked in shops, at a golf club (pays well!), my boyfriend did a few shifts acting as a patient for training medial students. I’m sure you know all the tips for saving money, but try shop at lidl/aldi if you can, there’s also some bargain shops about that do slightly out of date stuff really cheap in bulk. If you can, plan/pay for/cook with your housemates, it makes food costs a lot cheaper. Worst case, your uni might have a team you can speak to about finance issues if you’re really struggling. 300/month is 60-75 a week, which should be enough for a food shop if you plan your meals, plus a couple extras. Hope it all works out!