Can a cat think. What goes on in a cat's mind.?

Yes. It's easy to see the thought process in action when a cat is trying to figure out a problem. Cat: "The door is closed and I want to open it; I will try butting it with my head. No? Then I'll try pulling at the bottom with my paw. No? Then I'll knock on it with my paws until the human opens it for me." Very clever cats have even more sophisticated games. My Siamese once spent an entire day figuring out what objects she could and couldn't put inside a circular track, and which would roll around the track if they fit. She ended the day with two balls and a mouse in there, all rolling around.

We won't really know what the thought processes of cats are like specifically until we can communicate with them in a common language; when gorillas were taught sign language, it turned out that they universally had opinions on religion! (And not the same opinions, either.)

Keep in mind, however, that cats are easily confused by technology. They have no idea why they can't catch the laser pointer dot, or why the house can be a different climate than the outside. Also, their short-term memory is not as good as ours and they're somewhat more distractable. For example, if they're hurt and you give them painkillers, in the absence of the pain they'll quickly forget that they're hurt.