We don't have one yet (we're working on the documentation now, expected for the official 5.2 release), but there are examples in ProGet itself for: adding packages: click the Add Package button on the feed overview page after you've added one installing packages: once you have a package in a feed, browsing to it will show you how to install it with pip

Yes, ProGet supports this. However, you will need a paid version of Chocolatey in order to do that https://chocolatey.org/faq#i-would-like-to-be-able-to-offer-my-non-admin-desktop-users-an-option-for-self-service-type-of-installations