Try to find an active team with a full 50 members, or as near as possible and apply. You’re probably looking for Gold I to Gold III. Don’t be afraid to try other teams, but it’s decent to give your leader or an officer notice if you’re going to leave so they can prepare to replace you.
We kind of operate on a weekly schedule due to events - your event points only count toward the team you’re on at the start of the event (sightly simplified), so people tend to change teams mostly on the between-event days, Monday evening through Wednesday morning in US time.
Serious teams are looking ideally for members that log in at least daily and will participate in every war and event. Wars affect league placement and daily egg tokens, and group participation in events affects team achievement and team rank rewards. Find a team that’s playing at the same seriousness and activity level and with similar goals if you want to be happy.
Some teams have a feature called atlas that has become a big part of the game. You can’t use atlas until level 25, so figuring out whether you want it and getting an atlas team is not urgent. If you’re online all the time and like to help i suspect you may like it.