how are yall making friends outside school??

I want to make some friends outside of my school. I did a program last year and made five but it wasn’t long enough for us to start actually texting consistently and now I just like the occasional instagram story. I’m trying to look for more programs like this (it was an artsy museum volunteer thing 3hr every thursday) but I’m not finding anything + my hs career is ending soon and the ones i do see are geared towards 15ish aged people (i am 17, 18 soon)

I have a job and work with people my age but it’s not progressed past a wave in the hallways (if they do attend my school) or joking at work. Do yall just go to community spaces and be social? Is it sports teams? Church? What are some things I can add to my life that can broaden my social circle is my question I guess, or just any volunteer/program/event keywords i could look up to find stuff that may attract people my age?

My school is small and the same folks since kindergarten, we have our people and our circles and we don’t usually have class w folks outside our grade level. Sooo yeah.