I just made a Steam account! Now what?

I haven’t played that many computer games, I saw counter strike was on here free to play and was like hell yeah, I hadn’t played that since original Xbox back in the day. I loved age of empires and age of mythology. I did play civilization 4? Not sure which one. I did like that. I have civilization revolution on my iPhone which I constantly play. But is there other good subreddits to follow regarding steam? Looking forward to hearing what everyone has to say!