Not seen anyone say this yet, but last year my partner and I were in a similar boat. Bumble (the dating app) has a “BFF” mode for making friends. It’s worked out amazingly for us and we now have a great group.
It can take a bit of persistence, and like dating, some won’t work out. But it’s a great way to meet potential friends, and even in relatively small cities you’ll find some people on there.
https://www.khanacademy.org/
Helped me get through my engineering degree. Absolutely the best maths education I’ve ever seen.