make sure you have the Sidebar visible. In the VIEW menu at the top of the screen, choose Show Sidebar.

Create a playlist and put the tracks you want on the CD into it.

Open the playlist and make sure there is a check mark in the little box that is just to the left of title on all of the tracks.

That done, put a blank CD into the CD drive, select the playlist in the side bar and then Right Click it and choose Burn Playlist to Disc.
You can also to to File > Burn Playlist to Disc.

If that wording does not appear, then there is a track in your playlist that your computer is not authorized to play.

There is a stop by step tutorial in the Help menu item in iTunes. Choose iTunes Help and then put Burn a music CD into the search bar

P