There is no doubt that Moses wrote and understood that he was describing the creation of the world in regular 24 hour days.
And there was evening and morning ... the first day ...
And there was evening and morning ... the second day ...
You cannot claim he meant something else without committing intellectual and grammatical suicide. If you read the words you cannot come to any other conclusion than Moses meant 24 hour days.
It is an entirely different question as to whether he was correct.
The point is clarified as to what God was saying, by Peter, HE is the WORD and there is nobody in the flesh since, that can ever know exactly what Moses knew or did not know, as we are not mind readers.