Board games. Either just standard board games and chat while you play, or something like wavelength, that's a question, or herd mentality to actually get to know people through the game.

Bank Robbery seem quite fun, I highly recommend it

Join a hobby group or club for activities you’re actually interested in. It could be anything: sports, board games, video games. That way you already have a common interest with the others, and you feel less pressure to make friends because you can still spend your time doing what you enjoy.

Walking around in the early evening and stopping wherever people are gathering.

I was just popping out for salad greens, and ran across a group of young people having a picnic on the sidewalk. They had way too much food and were offering to share it with everyone who passed by. I wasn't hungry but I sat down and joined the picnic anyway. Great people! I stayed for over half an hour and I'm so glad I did.

And this isn't a one-off. This is how I met my wife, too, sixteen years ago. You gotta be open to spontaneous experiences.

Rock climbing, go to your local climbing gym (if you have one) and take an intro class and then go hang out once you understand the basics. It’s such a welcoming community and people are really friendly and helpful towards beginners. Gyms also have new climber nights depending on the gym and those are great chances to meet people.

Team sports

That depends on what your interests and hobbies are.

Volunteering or similar work, like lending a hand at small local theater or sports events. Depending on the work they might involve some downtime when you can chat with others and get to know them.

Another one I have not read in this thread yet: seek out (or organize) activities in your neighbourhood.

Fighting games. There's a reason the FGC still puts so much emphasis on offline play. Go to your locals, go to majors, don't just sit there playing ranked at home!

Join a choir?

Larping works great for me.

Great question! I use Meetup and Bumble BFF. I'm old though...

You could try DND open play events at hobby shops.

Board Games!

Chess, book clubs, group running.

Dancing. There could be many different styles - see what seems interesting for you.

Boardgame events.

Sporty/exercise events (like, walk with others from X to Y).

I've never gone to one but I have a friend that highly recommends fuck up nights (https://en.fuckupnights.com/).

Apparently it's a group that like meets up and like tells each other how they fucked up at work/in life/whatever. Kind of works like a support group but also helps to develop public speaking in a super judgement free environment.

Not totally my cup of tea but it sounds super interesting.

War (crimes) you'll be bonded for live threw trauma

You're on Lemmy, so I'm assuming you're of a geeky mentality. If so, a local hackspace/hackerspace/makerspace would be a good bet.

On paper, my local one is a communal collection of tools we can all use. In practice however, it's an excellent social group for fellow weirdos. We just also have some really fun toys to use, when we need them.

https://wiki.hackerspaces.org/List_of_Hacker_Spaces

It's not fully inclusive of all of them, but a good starting point.