I accidently used a regular cloth and tap water to clean my LCD computer screen. It didnt work and there’s still smudges and other stuff on it. If I go out and purchase the proper cleaning products for it, will it be able to clean it right or am I screwed?

Answer:
Yes, some screen cleaner should solve your problem.
Answer:
you don't need to go out and buy any kind of proper cleaner,what i always use is alcohol and a very soft lint free cotton cloth,so it won't make scratches.just buy the clear alcohol and it will clean your LCD screen perfectly,it does mine each time and it will not harm your screen,but do it with the screen off and cool.I guarantee you it will clean it.