Question about team system

This is the first time I use this website. I created a team accidentally because my first submission failed and I just want to check if it is necessary to create a team before showing scores in leaderboard. So I have two following questions.

  1. can we modify team name? can we leave a team?
  2. is it possible to merge two teams into a team?(for example, I have 2 member in my team and X have 2 members in their team, can we merge? and how) I only see the button of “invite members”

Thanks in advanced.