How do I stop Apple Music from unexpectedly opening?

I am an extremely naive user. I have a nearly new Mac Air with nothing on it except what is loaded from factory. I do not use Apple Music.

What happens is I am simply on Safari and browsing web or using email. Apple Music pops up and covers the entire screen. There is no dock, there is no control bar, nothing. Just Apple Music. The one and only option is to click on Start Listening. Or to hold down the power button and then restart. I restart.

Half the time when I restart I am right back with AppleMusic covering entire screen.

All help articles I can find are for people with more complex problems. lots of apps. I really seriously have no apps, no accessories, nothing but the factory load.

If I get a clean page and attempt to open Music in the dock nothing happens. I try clicking the Music icon. Nothing. Double click. Nothing. Hold down on Music icon. Nothing.

I've read many community items describing how to access Music in Settings. All describe Settings menus that do not appear for me.

Whatever is happening seems to come and go of its own volition. Sometimes it goes away. Other times it just keeps coming and there is nothing to do but close the lid and try again tomorrow.

[Re-Titled by Moderator]