Need a solution for power query related work

Hi everyone,
Here i attached the Excel file which will pull the data from website and the url has the from and to date.I want to change that date without going into the power query editor every time rather i have to do it from the worksheet cells.So i made some functions and all and it is not working.In excel file tab named problem has the detailed description of what i exactly want.So kindly go through the Excel file.Thanks in advance