早飯=早餐 1.我在早上吃早餐 2.早上時，我吃早餐 you can say two different ways

Thanks so much

No, it is not correct. The correct grammar is just like this: 早上我吃早饭 or 我吃早饭 In English, it means "One the morning I have breakfast" Actually nobody say "I have breakfast on the morning", because "早饭" means on the morning, just like breakfast