Welcome to our forum and congratulations on your bengal baby. I hope you have taken her to the vet to be checked out. Most breeders require that in their contract. Just to get a clean bill of health and start a medical chart on your kitty.
MOST kittens do not have bathroom accidents. They use the litter box without fail. Thus, something medically could be wrong but I'm guessing your cat does not like the litter box. You should be using exactly what the breeder used as far as type of box (open or hooded) and the litter. I read the word "pellets" in your post and many cats hate pellets. They may be more convenient for YOU, but the litter box is for the convenience of your cat, not you. If you want the cat to go where she is supposed to go -- make the box for her and if you need another litter box somewhere, get one.
Make sure you purchase a cleaner made especially for cat urine as cats will go back over and over again to the same place if it is not cleaned properly.
Aluminum foil is a great deterrent, however, who wants to live in a space-age looking house that appears aliens are living there.
The key is to train her to not go on the things you do not want her to go on. This means having a LOT of things for her -- at least one cat tree, multiple cat beds that are HERS and hers alone.
Bengals are very social and want to be with their humans, thus make sure that you have plenty of laying spots where you cat can be comfortable. Mine is usually on a platform on the cat tree or his large bed on the ottoman. At night, he sleeps at my feet.
Having a bengal is obviously new to you. The breed can be challenging .... and there is plenty of info to read online and in this forum. Take advantage of the advice and enjoy your baby.