There are lots of Mac games in the App Store. Unfortunately, the 32-bit ones won't run on Catalina or later.
If you have an Apple Silicon Mac, and look in the App Store, you may find that some iPhone and iPad games are available for Macs. Because iPhones, iPads, and Macs have such different user interface hardware & software, some iPhone and iPad games may work better on Macs than others.
Apple has a subscription gaming service called Apple Arcade . You get access to many games for a flat fee per month. The games don't have "in-app purchases" to nickle-and-dime you to death. In some cases, this means that the Apple Arcade version of a game has fewer features than the regular version.
If you are into flight simulators, there is one called X-Plane that you can buy from the developer's site. I bought a much older version of this for a previous Mac … and might, one day, buy the current one. This application tries to provide a realistic simulation, so learning to fly a plane well has a bit of a steep learning curve. (Crashing is easy!)