Open the Settings app
Tap Screen Time
Tap Turn On Screen Time if it is not already enabled
Tap Use Screen Time Passcode
Set a Screen Time passcode
Go to App Limits
Tap Add Limit
Select the app or app category
Tap Next
Set the time limit to 1 minute
Turn on Block at End of Limit
Tap Add
Open the app and use it until the limit is reached
Enter the Screen Time passcode when prompted to continue using the app