Help With Pdf Form Date Formulas

I have converted an Excel spreadsheet into a pdf form using Adobe Pro. It needs to calculate a 14 day pay period by entering a begin date.

There are 'begin_date' and 'end_date' text feilds that are formatted to mm/dd/yyyy.

There are 14 text fields in d-mmmm format that need to adjust to the appropriate day and date based on the the "begin_date" entry. I have very little experience with javascript. Help would be greatly appreciated. Thank you!