Hey no worries, I'm not here to judge at all mate, happy to explain actually!
Ok, so a canvas app is like a chassis, and so you can't make it do anything to any datasource that has not been added to the app as a connectable datasource using a connector (in this case the SharePoint connector).
So in your app, you'd click the datasources icon:
Then choose add data and expand connectors, if you don't see SharePoint in that connectors list then use the searchbar in that overlay:
If the connection with your user details is listed then click it otherwise if its the first time then it might just make it for you automatically otherwise click add connection.
Now you'll be presented with a list of sites on the right-hand side, you can paste the direct link to the site if you have it, otherwise search for it if it doesn't already appear in the list of suggested recent sites:
Then you'll be presented with a list of lists within that site that you can choose to add to your app as a potential datasource. Tick the ones you need then click connect:
Now that we have the datasource in the app we can use an edit form with that datasource as the datasource:
click Insert > Form > Edit
Then choose your list when asked for a datasource, the app will then pull what it thinks is the basic list of fields ( each getting a datacard and some controls) for that datasource. One of these will be the attachment control, which is what I was referring earlier:
And in terms of the directly connected app - when you use sharepoint and edit items in a list, every single one of those forms that are there by default, are canvas apps that have been integrated directly into sharepoint, but that doesnt mean that a standalone app Can't be connected to sharepoint. Additionally, a 'create from sharepoint' app is actually a standalone canvas app with some pre-filled screens and controls that make a basic functional app but they are in no way locked down to sharepoint or to the visual/configuration that they come with.
A canvas app can have multiple different datasources, sql/sharepoint/dataverse/etc and even all at the same time 🙂
I would Highly recommend going through the following learning path on mslearn if you would like to know more about building canvas apps - that will give you a solid baseline to build on top of, and when you encounter issue while building then these forums are here to help 🙂
Create a canvas App in Power Apps
Cheers,
