Maybe English is not your native language ? (it isn't mine BTW :) Catcalling has never been acceptable behavior, and, in my experience, does not increase anybody's chances of meeting new people. Catcalling is not flirting.
As to how to meet women (take this advise with a mountain of salt, was never a ladies man, have been married for 20 years and never cheated, so haven't flirted in 20 years :), play the odds; join groups that do stuff that interest you, get in a position to meet women, and meet them as people first, make friends and then relationships might develop; (and if not, you have more friends, and had fun doing whatever you were doing). That is, don't go to meetups (or pokemon tournaments, or the church choir, or ...) to hook up, go there because you want to be there, and, chances are, if you meet enough women you will find your match.
As to how to meet women (take this advise with a mountain of salt, was never a ladies man, have been married for 20 years and never cheated, so haven't flirted in 20 years :), play the odds; join groups that do stuff that interest you, get in a position to meet women, and meet them as people first, make friends and then relationships might develop; (and if not, you have more friends, and had fun doing whatever you were doing). That is, don't go to meetups (or pokemon tournaments, or the church choir, or ...) to hook up, go there because you want to be there, and, chances are, if you meet enough women you will find your match.