Our new Mac does not have a CD drive. I guess no one uses CDs these days. I still cruise second hand shops to look for old CDs, mostly to replace albums I used to own. I have several discs I wanted to enter into iTunes but without a CD drive I needed an alternative. Fortunately we still have the old computer that does have a CD drive. With that computer on the same network as the new computer, it’s possible to enter a CD disc into iTunes on the old computer, then transfer the music files to the new one and then enter the album into iTunes.
File sharing must be enabled on the computer with the CD drive, using System Preferences>Sharing>File Sharing. Both computers are using the same WiFi network. On the new computer I used Finder>Go>Connect to Server and Browsed for the old computer. Once connected I could navigate to the iTunes music under Music>iTunes>iTunes Media>Music. The album was then dragged to the desktop and then entered into iTunes using Add to Library and selecting all the songs and clicking Open.
Note: After upgrading to Catalina OS, iTunes is renamed to Music, and the Add to Library function wasn’t working as I expected. Instead I used Import and selected the album folder. To add artwork, Get Info on the album, click yes to editing the info, then select Artwork at the top, then Add Artwork and select a jpeg of the artwork.