When an iOS application is launched, a request appears to track your activities, where there are the options "Allow" or "Ask App Not to Track."
The activity tracking request occurs when you launch all of your installed iOS apps after updating to iOS version 14.5. You will still be able to use all the features of the app, regardless of whether you allow the app to track your activity. You can change your mind at any time in your phone's settings under Privacy > Tracking.
Detailed information is available on the official Apple website in the article: If an app asks to track your activity.