This receiver is intended to drive hobby "servos". These contain circuitry and a motor that positions a shaft/lever arm. The shaft is capable of only rotating 45 to 180 degrees, depending on the servo. In the airplane they were used to control the small movements of the flight control surfaces...and maybe the throttle. However, there are ways of modifying servos to get allow continuous rotation, and direction control, to drive wheels...or a tank track. There are a lot of web pages that tell how to do it.
You then use the servo shaft the same way you would a motor shaft...to drive your tank track. Actually two hacked servos, one for each track. Independent control of forward and reverse of each servo gives you forward and reverse motion, and differential steering. Not knowing the controls on the transmitter...you do have one?...you'll need to play with that.
Enlist now and maybe you could drive one of these Tamiya Tank. Just add a pea shooter and you could be doing some real damage.
Using the Tamiya tracked vehicle kit with a couple of standard servos might work, it would be "very tight" due to the back to back height. Using dc motors adds another unnecessary layer of complexity, but is do-able as shown by the picture.
There are several affordable R/C tanks that shoot Airsoft pellets...
How big a tank are you planning to build? Hobby servos were designed to control, pretty strong, but I don't think they can handle a lot of weight. There is a circuit (ESC - electronic speed control, I think), that converts the servo signal, into a voltage for driving a DC motor. They use them for R/C cars, well land vehicles... Believe you get forward/reverse and speed control.
In most countries the frequency for aircraft is completely different to that for land vehicles. Using this transmitter to operate a model tank may be illegal in your country. There is a very good reason why aircraft have an exclusive frequency.