Which is the place that cats love to be scrached?

If you mean a Scratching post my Cats naturally scratch on places near where they sleep. So putting it near their bed about 4-5 feet from it will allow them a place to scratch at when they stretch. If you mean where does a cat like to be rubbed or scratched it varies on the cats. Some like down their spine gently, some like the top of their head others love their chin, others love their bellies, and others love the length of their paws, Uusually if you hold out your hand and start moving your fingers like you are going to rub they will direct you to where they want to be scratched others live their tails, and some like the their butts rubbed that annoys me my cats have learned I refused to do butt rubbs lol... - DNatureofDTrain

you mean like a scratch post??

Most cats don't like to be scratched at all,at all. They like to be stroked at the side of their heads and under their chins. Most cats also like to be tickled behind their ears, but cats are very individual, so you'd have to find out about the one you have in mind.

Mine loves to be scratched on his head.

Going on the experience of owning several cats over the past few years, they seem to enjoy being tickled on top of the head, just forward of the ears. You might have noticed how a cat will encourage you to do this by pushing the top of its head towards/into your hand. For example, if you reach out to stroke a cat it will often stand up on its back legs and push its head towards your hand. Incidentally, don't assume that a cat will like its abdomen being stroked. Some do, of course, but many cats interpret such attention as a threat and to have four sets of long claws suddenly grab your hand can be, quite literally, bloody painful! Anyway, enjoy your feline friend.