Yes, and eye infections are rather common among kittens as they are just about to open their eyes. If you notice pus coming out of the eye socket, or that there is crusty material keeping the eyelids closed, you should take your kitten to a veterinarian for examination.
It could be an eye infection. Use some warm salted water and cotton wool to gently clean the eye area and visit the vets to get some antibiotics to clear up the infection.
The most efficient way to clear up red eyes is to use over the counter eye drops to keep the eyes lubricated. Sometimes if you blink frequently it can get rid of the redness as well.
Yes, kittens can be trained to use a litter box.
Good, I know that kittens use their wiskers to sense if predetors are around them or not.
When kittens are young they don't clean their own faces and rely on their mothers (or you) to do it for them, so this is totally normal. You can often just stroke it off their face with a clean fingertip, but if it's really crusted on you can use a washcloth soaked with warm water.
It is irritated. The best thing to do is to wash it out with cold water, then use a hot compress wrapped in a towel and put it on your eye(s). If the stinging continues, consult an eye doctor.
If the question is "Do kittens make messes", then the answer is yes, and Mom cat cleans them up, until she has trained the kittens to use the litter box.
Use cold cucumbers, tea bags, and some moisture cream, this suff works!
No, it can't be used. It will cause irritation in your eyes. Also visibility will not be clear.
No, 100% no, if anything increase humidity slightly
no its good for cold climate for hot climates clear roofs will be a good use