sharepoint 2013 schedule a workflow to run monthly

I am asking the following question since this is my first project working with SharePoint 2013.

The goal I want to accomplish is the following: 1. Create a custom list and willt start a workflow when the user clicks the 'save' button. Two columns on this custom list will be start and end date. 2. A person will either approve or not approve the custom request. 3. For the requests that are approved, the user needs to submit monthly updates on the progress of the original request. The start and end dates will guarantee that the monthly updates by the user has been submitted.

My questions are the following: 1. Would you tell me how to have a monthly workflow setup that is based on the start and end dates? The monthly workflow will tell the users that they submitted the request within the timeframe or not. The user may also be told they submitted the request successfully or not when they submit the original request. 2.Can you tell how to setup a workflow based upon if a user accepts the original request or not?