I think charge is to be understood as "payload" in this case.
It's approximately 20 tons to LEO, 7.5 tons to GTO.
Horus is right though, there's google for that. If you need some delta-V calculations or that kind of things that's OK to ask because you'd need some maths/physics class and google can't answer that. And believe me, Horus will be happy to provide you with all the calculations you need. But if you need the dimensions or that kind of things, Google can answer that kind of basic questions. That's how we would do it too, we haven't followed any kind of Proton classes, we are no better on this.