Apple Music vs Downloaded Music Sync

Hi Everyone,

I am trying to find out what will happen if I sync my Apple Music. Bit of background - I have a ton of music that was downloaded years ago. I now have a large part of that on my phone in what would’ve previously been iTunes. It is now separate from Apple Music - but they all fall under the same app now on iPhone. I also subscribe and use Apple Music separately. Sometimes I’d like to add a song from Apple Music to one of my own made playlists but Apple says I need to sync. I purposely do not sync and have selected “manage music manually” on my Mac.

I guess my question is - is there anyway to combine the two? To keep all of my downloaded music on my phone as is and combine with music from Apple Music? Can they exist together?

it’s a tall ask to go through the thousands of songs already on the phone, brought over from my computer, and try to organize that all over again.

I did try using iTunes Match to clean up some of it but unfortunately did not solve my problem of having the two libraries of music exist together in one neat location.

I hope I am explaining this clearly. In my head it makes sense but not sure I’ve written it down clearly.

thanks in advance for any help you can provide