I am assuming that you have checked the basics on your vehicle, ie. oil and coolant levels?.
These two problems could be related but foremost to address is the overheating problem as if you don't you will not have an engine to rev at all.
If it is overheating so soon after starting then it is either very low on coolant or the coolant is not circulating due to a faulty thermostat or the impeller on the back of the water pump has come off or is damaged or there is another restriction in the cooling circuit. If you are unsure of checking these things yourself then it should be checked by a professional and do not drive it like that it will cost you a fortune.