Why won't iTunes play my music????

I bought a new iMac and would like to play the music I have. I can play on my macbook and my iPhone. I see my library in iTunes but all albums have a cloud next to them. They will not play.

I have "authorized my computer" and it is confirmed in my account settings. However it says that only one device is associated with my iTunes account.

I don't see any option or method of associating the new computer.

FRUSTRATING to say the least.