YouTube’s built-in feature for playing games inside the app is called Playables.
YouTube introduced Playables as a collection of lightweight, interactive games available from the YouTube Home page and the Explore menu. The games are designed to run inside YouTube rather than requiring users to open a separate gaming service or install a traditional console-style title.
The catalog has included games such as Angry Birds Showdown, Words of Wonders, Cut the Rope, Tomb of the Mask, and Trivia Crack. Availability and the exact selection can vary by account, device, location, and rollout stage.
Playables is easy to confuse with Google Play Games, Apple Arcade, or older instant-game platforms. Those are separate gaming services or distribution systems; Playables specifically refers to YouTube’s own in-platform games feature.