Complete Quest and Earn Gems Brawl Stars

You can earn gems by completing the daily quest available in the game. Choose from the events to play that are present beside the Play button. So, by playing different events available in the game, you can collect loads of Brawl Boxes the contain gems. Another way is to choose the trophy road option.

Also, remember to unlock the quest option, you need 300 trophies. So, play more to unlock more events and get access to gems in Brawl Stars.