Apps on the App Store are rated by age. To manage the age rating, the device can download, go to Settings > Screen Time > Content & Privacy Restrictions > App Store, Media, Web, & Games > Apps
Apple's App Store ratings
4+
Apps in this category contain no objectionable material.
9+
Apps in this category may contain mild or infrequent occurrences of cartoon, fantasy or realistic violence; and infrequent or mild mature, suggestive or horror-themed content which may not be suitable for children under the age of 9.
12+
Apps in this category may also contain infrequent mild language; frequent or intense cartoon, fantasy or realistic violence; mild or infrequent mature or suggestive themes; and simulated gambling which may not be suitable for children under the age of 12.
17+
Apps in this category may also contain frequent and intense offensive language; frequent and intense cartoon, fantasy or realistic violence; and frequent and intense mature, horror and suggestive themes; plus sexual content, nudity, alcohol, tobacco and drugs which may not be suitable for children under the age of 17.
Source: https://apps.apple.com/mn/story/id1440847896