Your in luck. The answer to both of your questions is yes.
The Wi Fi is different amounts depending on how much time you would like to buy. Watch for specials each day, where they discount the minutes, or even add minutes on to the package to get you to buy.
Carnival receives it's TV feed from Denver, so if they can watch, so can you.
You should have several stations to choose from.
More fun is to go to the sports bar, to watch with others.
Have a great cruise.