Repetitive background task in UWP - C#

I need a Files/Folders Backup app in (uwp) universal windows platform C#, which automatically backups user selected files/folders to a specified location, at user defined time/every-day/selected-days/week/monthly. * App should load when user logs into the PC. Run in background and should do backup tasks automatically without user interaction or need to open the App manually, except once when he sets the files & recurring time. * User should be able to save Multiple tasks. A task is backup set with it's own time and files/folders. -------------------------------------- (I am a friendly, co-operative & honest person, My advice is: You should do this project in 3 phrases, to minimize discrepancies, I will release corresponding milestone after every phase)