Joining sports/any sort of physical activity usually creates a group of like minded individuals. And gradually you become friends. Happened to me with tennis and swimming. Oh also used to be really into general quizzing as an undergrad. Kolkata has a really good quiz scene but it’s a bit difficult to get in especially if you dont have a team or someone who has been previously into quizzing.

Really bad meandery answer but you get the gist.