How do I send a song via text that I have in my library, it says not allowed in US, wth does that mean? I paid for it, have the disc, loaded it to my phone, I don’t understand the error or lack of compliance by Apple?

It sounds like you may be conflating a number of things. Sending the file would be copyright infringement. So long as you retain the physical media, you can retain a digital copy. Digitally purchased music is a license granted to you, not ownership. If you have purchase sharing enabled, or share Apple Music, you can share those songs. Or, you can share links to music through iTunes/Apple Music that a subscriber can then purchase or listen using Apple Music.

You can purchase individual songs in the iTunes Store.