Q: how do i import my library from old computer to my mac

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(128699)

First, consider using Migration Assistant to move everything from the old computer to the new one.

Moving an iTunes library: Quick answer if you use iTunes' default preferences settings:  Copy the entire iTunes folder (and in doing so all its sub-folders and files) intact to the other drive.  Hold down the option (alt) key (shift on Windows) and open iTunes.  At the prompt to create or choose a library choose the copied iTunes folder.

When this is to a new computer put the copied iTunes folder in the default location of Macintosh HD > Users > *User Name* > Music  then you don't even need to start with the option key held down, iTunes will automatically look for it there.  (Make sure there isn't anything already in the iTunes folder there that you want to keep since you will be replacing it with the one you are moving.)