So in this game, raid groups are rarely free companies. Your best bet is watching the party finder(opened with the party tab>Party Finder). Sometimes there will be groups advertising looking for raid members. If you don't do that, your next best bet is finding discord channels and maybe visiting the reddit recruitment sub. (https://www.reddit.com/r/FFXIVRECRUITMENT/)

I personally don't know of any discord channels to point you at. Personally the lodestone freecompany listing is useless.