Can I use normal soap to wash my 3 month old kitten?

take a warm wash cloth use JUST warm water, there is no need to wash a kitten
and never use people soap NEVER

I definitely wouldn't. There can be detergents and other chemicals that could harm the kitten if ingested, since cats do bathe themselves. There are cat shampoos, sprays, and pet wipes that work really well. My best recommendation is Pet Head or Whisker City pet wipes. They are gentle and good for kittens, especially when they get litter or anything else stuck on them.

There is a real danger of it going into shock - which is why you should never, in a billion years, wash a kitten. So, no, you cannot use normal soap to wash/scrub a 3 month old kitten.

if you have to bathe the kitten i would go out to the store and get a bottle of shampoo especially made for cats/kittens. make sure you read the label to see that it is safe for your age of kitten some labels have "do not use on kittens under a certain age)

A warm damp washcloth is best (a wet cotton ball is okay too). You must keep her as dry & warm as possible once you have wiped her off (Do not use a heating pad- fill a sock with a few handfuls of uncooked rice inside it and microwave till warm, it works well...test the temperature of it on your skin first so you don't burn the baby).

I would either use warm water or kitten-safe cat shampoo. It's okay to wash kittens, but be sure to keep your kitten warm until it's all the way dry. Paper towels work surprisingly well to dry them off with once you've used a regular towel. Good luck!