When calculating monthly cash flow statement, how we calculate the receivable and payable amount only the difference? or the entire amount?

I didn't get your question , you calcualte using actual figures accourding to tranactions catigory in positive or negative ( ) way , you get total for every catigory  and all in one column until you reach total balance and you should mention the change in cash in the end .

From the way you asked the question, i understood that you are using the indirect cash flow method.
anyway when you calculate the cash flow it has to be the difference between closing date and opening date for the balance sheet.