I need to fix it can someone help me
Overfilling your oil won't necessarily overheat the engine. Might be something else. But if it is overfilled, it will run horrible and blow out some seals and gaskets. If your due for an oil change, have one done and refill to the proper level, if you just did one, drain the oil into a pan and re-add to the proper level and save the rest for top offs. You might want to look at your cooling system since your overheating.
Have you added coolant lately? You could be low on coolant to overheat.
Looking for a Used S60 in your area?
CarGurus has 7,740 nationwide S60 listings starting at $1,988.
Search Volvo S60 Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Volvo S60 Experts