Depressed WFH - how to be social again?

I've been WFH fully remote for 2 years now, 26M and I have become a complete hermit. I work from home, game in my free time, eat, sleep, and that's about it. The only person I interact with regularly is my girlfriend. I rarely, like once a month at best, go out to hang out with friends and it's usually just one-on-one with one particular friend from college. How do I reestablish a social life? I'm in a city where I don't know anyone. I feel stuck, depressed, and hopeless. I love my job and my whole team is great, but I feel like a zombie outside of it. I actually miss going into an office but that isn't even a possibility for my team. I'm thinking about starting a gym membership just to get out of the house to do something. Any advice would be appreciated.