If you eat rice, fish, and soup for breakfast everyday then you must use present simple, 'For breakfast, I eat rice, fish, and soup' or 'I eat rice, fish, and soup for breakfast'. If you want to say what you ate this morning or yesterday etc 'For breakfast, I ate rice, fish, and soup' or 'I ate rice, fish, and soup for breakfast'. Both examples are fine. However, if you are having breakfast now 'I am having rice, fish, and soup'. There is no need to say the word breakfast because the listener knows that it is breakfast time. If you are talking about breakfast in the future and you have already decided the food that you want to eat then you can use the present continuous with going to, 'For breakfast, I'm going to have/eat rice, fish, and soup' or 'I'm going to have/eat rice, fish, and soup for breakfast.' One of the previous posts on this topic said that 'What are you having for breakfast?' is present perfect. Ignore that because it's incorrect. Present perfect is 'What have you eaten for breakfast?' The answer would be 'I have eaten rice, fish, and soup.' This tense is used when breakfast time has passed and the listener doesn't know what you had/ate for breakfast.

it`s correct, but it`s more common to hear it " for breakfast, i have rice, fish and soup "

I GOT IT. Thank you so much for answering my question. I really appreciate it :)

It also depends on the tense you choose.....What will you have for breakfast? (Future) For breakfast, I will have rice, fish and soup........what are you having for breakfast?(present perfect) I am having fish, rice and soup. .... What did you have for breakfast?( Past simple) I had .....