Ok about to buy a li po battery for my savox 1268 servos do I even need a cut off and what's the way to program it

You do NOT want a LV cutoff on a receiver battery. Think about it, do you want your receiver battery to just cutoff while you are running the car at speed? Sounds like disaster waiting to happen to me.

Just charge it regularly. You should be able to get more than an hour of running on a full charge and if things seem to be getting sluggish, stop.

Just get a cheap lv alarm from ebay. Plug it in to the balance port and when you hear the alarm, stop the car when you can and recharge the lipo.