How do you make friends in adulthood?

I’ll be 30 in few months this years. I spent almost the entirety of my 20s friendless and I really hope that my 30s can be different. I don’t waste to spend the entirety of whats left of my youth friendless. I have my partner but I'd like to have more than one person in my life.

Looking on internet, I've read advices to go to places where to find people with similar interests. The issue is that the only place like that in my country have almost only cis men, in addition of having social anxiety, and I’m more comfortable with people identifying as same gender as my assigned gender and nonbinary, and maybe ND because almost all my internet friends are ND. (It’s not to exclude others people, but by trauma of always being judged negatively by others folks and rejected for being too much in my world or too obsessed over my interests).

I m on internet communities about nerdy stuff I like filled with people who are just like me so we connect so well but they are all in USA and I from Europe.

I desperate of finding a friend in my city. I don’t know how to do.

However other people in the communities seem to have friends just like them. Maybe because it’s easier to find irl friend through if you live in America.

I have an easier time interacting on internet first before real life but people are rarely in my country so let alone in my city.