A:AnswerYes, you will have all those apps and more, you even can use the same account you have in your tv to put it on the firestick, some apps are free and some others require monthly payment.
A:AnswerNo, you do not.
You can download most of the common apps that you would find in a smart TV.
This is the advantage so that you can continue to use the regular (non-smart) TVs, as long as they have a HDMI input.
A:AnswerUseless answer because "The Tennis Channel" is NOT the same as the Tennis TV app. They are two different services. For example, on my own Hisense Google TV, the Tennis app is available, but supposedly the Tennis Channel app is "not compatible" with the TV.