Just open the app and scroll down to the match you participated, click on it and there you will get the Room ID and Password before 15 minutes of match start time. Make sure you join the Room within 15 minutes before match start time.

Yes, you can team-up and play with your friends in a same team in a match. To do so, make sure you and your friends have registered for the same match and when the Room ID and Password are shared, make sure all your registered friends and you join the room and take the same team slot.

Well, there are several reasons why you get kicked from the room even after you register for the match. Some of which are:

You registered incorrect PUBG Username and hence our filtering team did not recognize you.

You joined with new PUBG Account or with the doubtful account which is against EsportsXO Fair Play Policy.

Joined with PUBG Mobile Account with Level less than 40.

Invited Unregistered Friends to the Room.

Kept changing position in the room.

Using Emulator to Play in Non-Emulator Matches.

You can use bonus to pay the 10% of the match fee.