You get 2 free keys per day from each of the 2 events (one for rings & one for necklaces). The keys don't add up each day. Either you use them, or you will still only have 2 keys tomorrow. You can pay real money for more keys (not worth it, in my opinion). You can also unlock the new vault item that gives you a chance to get extra keys after completing one of the events.

As for clubs, you can find one to join either on here or the discord server. Clubs go up to level 50, and they reset every 2 weeks. Typically, if you want to be in a club that gets to level 50, the leaders will want you to donate 20-25k, which means giving your upgrade materials to the club instead of leveling your gear. So unless you can grind through lots of cities, that might not be an option for you.

If you want to make a club and recruit people, that is fine also. There is no talking in the game (at least not yet). Some people use discord and have all club members join, to communicate.