You have two things to deal with that require CO2 - carbonation and serving. I assume you're too late to carbonate naturally with added sugar, so you'll need to force carb.
To carbonate with a tank you'll also need a regulator, a short length of gas tubing, appropriate clamps for either end of the tubing, and a ball or pin lock quick disconnect for the gas in valve on the keg. You'll also need a place to put the keg where it's cold while you're carbonating, at least it would be most preferable to do so.
You can use the same equipment for dispensing if you like; that's what we do when we have a permanent kegging setup. However, you may also consider a "keg charger" for dispensing, like this one:
https://www.amazon.com/Charger-Connection-Picnic-Dispenser-Cartridges/dp/B00OSGC3MU/ref=pd_sim_328_4?_encoding=UTF8&psc=1&refRID=WDFC9T0DPKCT00TGGB63
It uses CO2 cartridges and is much easier to travel with than the whole tank, regulator, and tubing setup. It will not carbonate the beer, but it will push it out adequately to produce the expected flow rate and head.
The biggest pain with keg traveling is sediment. Kegs are best left untouched once they are tapped, so the beer can clarify. If you move it, you will stir up a cloud which will need to re-settle in order to keep the appearance looking nice. Of course if you're serving out of red Solo cups it may not matter!
I have purposefully brewed cloudy beer - like hefeweizen - when I've chosen to bring kegs to other venues. Either that, or see if you can get it there a few hours early and put it in place ahead of time.