Apple Music is a online library of music for a monthly subscription fee. As long as you setup your Windows iTunes to have Apple Music all music will available. If you add an album to your Apple Music Library, it will appear on all of your devices Apple Music Library as added.
I do not believe there is a way to "Purchase" music in Apple Music, it is a ...
There are three ways (that I know of).
The first method is going to System Preferences -> Users and Groups -> Login Items
and clicking the - button when selecting an application to remove it from startup.
The second method is to right-click the application in your Dock, then uncheck Options -> Open At Login.
The final method is going to Finder, ...
From what I found there is no way to add an audio file into Podcast application: as of macOS Catalina, it supports only subscribing to RSS feeds. The only way built-in way to listen to the separate podcast episode is to find it via application search and add it separately.
However, I found out that you can listen to any audio files including MP3 the same ...
A song loved on your computer doesn't mostly show up as loved on your iphone, while a song loved on an iphone is always showed as loved on a computer version of Apple Music.
Solution is to first add the song to your library on your computer and then loved it. Then it's auto synced to your iPhone.