try watching some streamers on twitch, they are usually pretty good at finding fights. not sure who mostly streams in lowsec frigs these days though.
for t1/faction frig PVP I agree that FW zones are the best bet. Novices are locked to only t1/faction frigs and most of the people in them are there for a fight, so go for it! of course if you have a bad matchup they might run away, like someone else said a griffin navy no one wants to fight. Or if you are in a pirate faction frig. I’m guessing many will stick around but don’t get offended if they warp out.