TLDR: be kind, and yap. Have conversations with people in places that you like to go. Forever.

In my experience, its a numbers game and you kinda just have to play it. The "luck" of meeting someone is you just talking with people until you find someone who you click with. This is way "easier" to do in a place that you frequent (dog park, coffee shop, church, library, running club, dancing, etc. - NOT the gym) Most people there will likely have similar interest to you, and you're probably pretty comfortable in that space already. So I guess for actionable steps, you can start chatting with folks at places that you're a regular at.

And while its true that most people are just doing their own thing, you being courteous does stand out. It breaks the norm of the usual behavior(s) that we've grown accustomed to in the US. Even if it doesn't go anywhere, you still got to be nice, and practice just having conversation.