In APEX LEGENDS, you can play in teams consisting of up to three people. When you start the game, you can invite your friends.
To invite friends, click on the empty area near your character. This opens another window in which you can choose which friends you want to invite.
Remember, you need to cooperate. Don't split up - you need to be ready to help each other anytime.
Your team should also test out different characters to create the best possible line up. Remember, a medic is extremely important - this person can heal your team.