While in a lobby, you can use a mic to communicate with other players. You can also mute other players from the lobby’s members list. You can only mute players with voice chat enabled, which is represented by a speaker icon beside the player’s name.
During team matches, you can only communicate with members of your own team. In the other hand, you’ll be able to communicate with all players participating in Battle Royale matches. By default, voice chat is off. Enable it by going to Options > Sound > Voice Chat.