How do I buy and download music from Apple Music on my iMac running macOS Catalina 10.15.7?

I can't find where to purchase a song on Apple music.

I have not downloaded music for a long time, and everything seems different.

I can find the album on Apple Music. But I can't figure out how to buy and download it.

I also don't know if I need to get a subscription of some sort that I now do not have

Can you help?

This post does have text. But it says to me "your post must include text." what is the problem here?

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