Opinion on age difference in relationships

I think maybe 1 to 5 years age difference. Also in my opinion there is definitely a difference when you are a minor and when your a adult. Like for example my friend, let’s call them Jude. They are with someone 3 years older then them and when I think about I think mostly about the grade they are in not in and not there age. Like for example imagine you being in 10th grade and saying “I’m dating a 7th grade” That sounds wrong af. Maybe I’m in a little over my head but still, it’s weird