Why is my fans sound is very high

That usually indicates an overheating CPU so don't run the computer until you have investigated the possible causes.

That model is about 11 years old so you may just need to clean the dust out especially from the heat sinks and fans - canned air is good to blow dust out outdoors.

Replacing the paste on the CPU heat sink is another good idea if it is getting crusty and dried out. It should swivel easily on the CPU once the clips are released otherwise replace. Be mindful of just using a tiny pea sized blob of the paste. There shouldn't be any oozing over the edges. The commonest error is using too much. Remember all you are trying to do is fill the microscopic pits on both sufaces.