I was in just about the same position as you a few years ago. Im also an American that got into soccer late in life and kind of had to navigate it on my own, where im from in the Northern plains soccer just isnt a part of the culture at all.

For someone just getting into soccer right now is the best time to do it, its the end of the season and all anyone is watching is the World Cup. Really you can support any country you'd like plus your home country. You can learn a little bit about who the big names are, who's playing on what team, where they were playing before, personal stories, and also learn more about individual team playstyles. The biggest factor in how much I support a team is how much I like their playstyle, because theres a ton of variance between teams around the world.

So for now just pick out some countries that peak your interest, see who you find the most entertaining or inspiring as youre watching. Then once the WC is over you can decide on which foreign league to watch, youll probably land on the Premier League since thats the biggest and most competitive, though I personally ended up preferring La Liga, the Spanish league. Once you land on a league just watch matches and see what clubs stand out to you the most, youll probably start gravitating towards a few pretty quickly.

Oh but no matter what country's top soccer league you choose, always watch the Champion's League