Is there any difference when we replace a new measure like SalesAmountproduct key in dim or fact table? and how we know the correct position?

There is no right or wrong way, but I do recommend to create a blank table and place all measures inside this table so that your measures remain in once place

Sorry, I don't understand, what do you mean replace a new measure? Do you mean placing a measure in dim or fact table?

Yes, Correct, this is what i mean