How the hell were you able to find FWB’s?

I swear whenever I go here I see how often many people being with someone & I was wondering HOW?! How do you even start? Is it easy or is it hard to find at least one person to be with? Currently in college & dont know where to begin other than going to events/activities I am interested in. Also before someone comments on joining clubs, I have & wont lie there are few to no women (chess, IEEE, woodwork, 3D printing, gaming)