Binary Release Download Link For Submitting An App

I went through the documentation for submitting an app but am unsure on the exact process. Is there a link to existing Manifest files that I can take a look at as examples?

Also does Flathub support uploading the Binary Release of the app only? I’m seeing that existing apps in Flathub are built from source through an automated process?

Is there a way to provide a link to the Binary Release and have the app installed to the Linux distro?

Find an app on flathub.org that is similar to yours. Go to Links → Manifest. There you’ll find a .json or .yml build file.
Source builds are preferred but binary ones are accepted as well.