How to Create and Edit ID3 Tags in iTunesby Laurel Storm
When your songs lack ID3 tag information such as album name, track number and artist name, finding the tunes you want to play in iTunes 12 can feel like you are making selections blindfolded. To add the missing information or modify incorrect details, use the song information window in iTunes.
Adding or Editing Tags
Right click any song and select "Get Info" -- or press "Command-I" for Mac -- to open the song information window. After the window opens, click any of the labeled fields to activate it, type in the information you want to add and then press "Enter" to confirm. If you change your mind, press "Esc" to deactivate the field and return to the original information. If the field corresponding to the tag you want to add is missing, click the "Add Field" button and select the field from the drop-down menu that appears. When you're done, click "OK" to save the changes.
Editing Multiple Songs Simultaneously
To apply the same tags to multiple songs at one time -- to group songs into an album, for example -- select them all, right-click any one of them and select "Get Info." When you do this, iTunes may prompt you to confirm whether you want to edit information for multiple items. Click "Edit Items" to proceed. Check the check box labeled "Do Not Ask Me Again" to suppress any future confirmation prompts.