I have recently discovered that my car makes a terrible screeching noise whenever I turn the wheel in rainy weather. Last sunday it was a little rainy and my car was screeching every time i turned the wheel. However, it was pouring yesterday and it didn't have that problem. My friend said the belt on the power steering pump needs silicone or something like that. The actual pump is not broken. Question is, how do i put silicone on the belt or do i actually need a new belt?

 

your buddy sounds correct. belt= squeek, grind/whinning= pump
that belt conditioner is crap ive attempted many times to use it and its always temporary(or makes it worse) and makes a mess of the engine bay. serpentine belts are a breeze to change out. there should be a routing image on the underside of the hood or fender well or front clip somewhere. if the belt is older its become more of a plastic then a rubber and probably stretched. i have had a higher success and cleaner outcome using a piece of sand paper on the belt while running instead of the belt sprays. BE CAREFUL NOT TO LOSE A FINGER.
B

 

https://www.2carpros.com/diagrams/nissan/maxima/1997

belt diagrams

 

There are 2 possibilities - the belt needs to be replaced or tightened.

 

UPDATE: Upon further investigation, i've come to the conclusion the power steering belt needs to be tightened, here's why; when i started my car and started driving, i would go around a wide bend at like 20-30 mph and there would be squealing. However, when i got to a stoplight, i turned the wheel lock-to-lock a few times and the squealing went away. Does this sound right?

 

Replace the belt. It is probably the original belt and 20 years old. They dry out, crack and stretch. Loose belts squeal.