Beyond all question, you can get gems through
Brawl Stars top up service. But upgrading the Free Pass can also get you some free gems. This approach sounds cumbersome and time-consuming. But if it were easy to get free gems, Supercell might go out of business soon.
Usually, the number of free gems in each Brawl Pass is 90. You can also get a small amount of gems by opening the chests. Although the chance is very small, if you play this game often, you can still get a lot of gems this way. Spend more time without spending money. As it should be.
So the best way to get gems is to buy the Brawl Stars Top Up service from third-party online
marketplaces such as U7BUY. You can enjoy the promotions when buying Brawl Stars gems there. It's possible to save a lot of money if you are lucky and encounter a big discount. So you should visit these websites more during holidays.
Besides, you can also Top Up Brawl Stars gems for your friends on the online marketplaces. Because they only need the user ID of the corresponding account to do a top-up.