Can I Add A Featured Artist to My Track?

Absolutely! Just make sure it is listed like this:
 
  • Example with 1 featured artist: Under Pressure (feat. David Bowie)
  • Example with 2 featured artists: Shortie Like Mine (feat. Chris Brown & Johnta Austin)
  • Example with 3 featured artists: Sweetest Girl (feat. Akon, Lil Wayne & Niia)
Adding a featured artist does not require any additional artist slots (that's good!).

Please note that if you have the same featured artist on all tracks of a multi-track album, stores require that they instead be listed as a Primary artist.