Last step for syncing MUSIC doesn't exist. And why doesn't Homeshare work?

I've never really used the iTunes/Music at their capabilities ... but recently I've decided to get rid of CDs and put the music into the app to stream it.

I follow the steps to sync my music across devices. The last step for MAC after "click general" that window to Sync doesn't appear. The MacMini is 2014 (I know ancient) and can only run 11.6.2 OS. The iPhone and iPad are up to date. Is this one of the problems as to why the "Homeshare" for the music Library is screwy? I created a playlist last night as a test. The playlist appears in the iPhone but the tunes are not correct. I even created another test 1 and they both appear, both with the same tunes. I deleted the original test from the Mac and it still appears on the iPhone. I see no way to delete the playlist from the iPhone.

I am attempting to use Homeshare vs paying $10/month to listen to my own music. Is this another hurdle?