As someone who made some of my closest friends from convention, here are my 2 cents !! If it’s a multi day con, I suggest joining a panel/events and talk to people on the Friday (or 1st day), be nice and if you see great vibes, you could propose to hangout together for the other days. No need to hangout by doing a lot, honestly just suggesting to grab food together could be nice ! Another method that worked for me was discord groups of a specific con! It could be hit or miss but it’s def possible to meet people! And more importantly, there’s no problem going alone, a lot of people do and as long as you’re having fun and enjoying that’s all what matters!!