Cartwheel confusion

Hi Target
I just would like to ask if theres a way you guys can explain how the cartwheel works, theres a separate app for that? Whats the deal with the receipts that you can upload after shopping? I just find it hard to understand, been looking for info online but the options on the others app doesnt show up at mine so.... I uninstalled the target app and downloaded again. Doesnt work, I downloaded the cartwheel app separate from the Target one and still ???????

If theres anything you can do to help out Ill appreciate it, I really enjoy shopping at Target.

Best Regards,

SS

Sahy S about Target, v9.0.1