早饭 = early meal
早餐 = breakfast.
Generally the same since they both are a meal early in the morning. However, the differences can be huge due to cultural factors when you are translating. For example, a western home breakfast can consist of just milk and cereal where as a Chinese can have a full meal loaded with meats etc; some Chinese may just have plain watery porridge and served with some preserved vegetables and Cantonese will have porridge loaded with seafood etc. Or if you go to an American buffet breakfast, there will be sausages, eggs, pancakes etc. So the image conjured will be different.