Cats will generally prefer a quiet spot away from main walkways and not too near their food. Having more than one litter tray is a good idea when you have small kittens or multiple cats. If your litter tray is on carpet it can be a good idea to put plastic carpet protector underneath.
Wherever you decide to locate the litter tray, make sure it is convenient for all, and won’t trip people up or get in the way. Once in place, it is usually easiest to keep it in that same location from then on to avoid confusing your cat.
The best place, at least initially, will be where your cat wants to go to the toilet. If they are repeatedly having accidents in one place it is easier to put a litter tray there, to build your cat’s litterbox habits, and then move it later.
If you do need to move the litter box, move it gradually towards the new location, rather than in one go, so your cat has time to adjust their routine to match.