Use multiple iTunes libraries on Mac
You can have more than one iTunes library. For example, you could have a library of holiday music that wouldn’t appear in iTunes the rest of the year. Or you could keep your music in a library on your computer and your movies in a library on an external storage device.
In the iTunes app on your Mac, choose iTunes > Quit iTunes.
Hold down the Option key while you open iTunes.
In the window that appears, do one of the following:
Create a new library: Click Create Library.
Choose a different library: Click Choose Library.
You can name your iTunes library (the folder containing your iTunes content and the iTunes Library file) whatever you like. For best results, if you create additional iTunes libraries, don’t name the new libraries “iTunes” or “iTunes Music.” Make sure each iTunes library has its own unique name so you’ll know which is which.
In each library you create, you can select different preferences for the iTunes Media folder, the types of content that are displayed, parental settings, and the library name. To set preferences for a library, choose iTunes > Preferences while using the library.