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The point of that foreground service is to have such permanent notification visible, that is the way Android designed it, they also allow to hide the notification, that is on the system side not something an app can do on its own since otherwise apps could secretly put hidden/invisible permanent notifications and be always running in background without you noticing

To hide it long-press the notification and options should appear or search on internet "how to hide permanent notification Android 10"

(Note: it is better to create posts focused on one topic/question than making several random questions in a single post, that way it is easier to digest and reply on-point and not to overlook some of the questions or feel overwhelmed, also more useful for readers that will more easily discover posts about the question they are looking for)