Hey, hon, you may want to utilise the questions thread in the future, but it seems right now you aren't in a club, so you can join any one you'd like as long as you meet the stats requirement. For future reference though, you can go to the club's main page, scroll down to club settings, then choose to leave from there.
You don't have to leave a club to join a new one anymore. Just click on the join button of the new clubs and you'll get a prompt asking if you're sure you wanna leave your current one before you join