itunes is missing on hd

What operating system are you running?

iTunes was removed from macOS Catalina. If you are running Catalina, you have the TV, Music and Podcasts Apps in its place.

See if you can find the file(s) using one of these programs. If you go Finder/View/Show Path Bar, it will show you where it is located.

EasyFind – Spotlight Replacement.      

Find Any File.   

Then unless you manually uninstalled it, iTunes should still be there somewhere.

Use the Start Menu search to find it, or ask Cortana for it, if you have her enabled.