Welcome.
How is your current set up wired?
If you are using a cable box, you will need to run a HDMI from the cable box to one of your TV inputs so it can get the sound and picture.
If you have that already, be sure your TV is on the correct input to play from the cable box.
I'm not familiar with the Pioneer or it's age, many more current receivers also offer a bypass feature so you don't have to do the above second connection.