When my boys were little they were happy to have plain oats with a little honey or golden syrup. Flavoured oats in packets and boxes later became the, “can we get those” item in our house. No. So I started making my oats with chocolate or strawberry flavoured milk, or we’d grate some fresh apple with sultanas/raisins or cinnamon in, then there is no need for extra sugar. I like whole oats best. I do them in the microwave and it only takes 5 minutes. Your favourite flavoured milk can now be your favourite flavoured oats.
Make your own quick oats by putting them in a food processor and blitz, be careful not to to end up wit oat flour.