You have already seen that you share an app to deploy it. Sharing an app with a user authorizes that user to run the app.
Users need to be licensed for Power Apps. Licenses for Power Apps are included with Office 365 E3/E5 and Dynamics 365, but these subscriptions only cover the Office 365 and CDS connectors. If you want to use other connectors, then you may need to purchase and allocate separate Power Apps licenses.
Sharing an app allows a user to run the app. You need to allow others to edit and change the app separately.