The following steps show you how to import your music that stored in your computer into your iTunes library. Keep in mind the location where you have stored your music and start the process.
- Launch your iTunes.
- Find “File” tab on the menu bar and click it. 
Click “Add File to Library”
- Find “Add File to Library” option in the drop-down list and click it. A pop-up will appear on the screen which allows you to select music from your computer.
- Navigate to the location where you store your music in your computer in the pop-up with the navigation bar to the left of the pop-up.
- Select the music you want to add to your iTunes library and click “Open”