Buy a pair of kittens. You'll learn in a hurry. You'll want your tom quarters all built & ready for when the boy starts spraying.
You should get information from whatever cat registry is used in Spain.
Information like what you need to do for a cattery name. Do you need several cats to get a cattery name. Each registry has a set of rules or conduct guidlines. You need to follow registry guidelines, so that you can register your kittens.
With one pair of cats, the worst thing that can happen, is if it doesn't work out, you have to alter both of them. Whoever you buy your cats from can answer lots of questions. A few basic things that might save you some grief. Only buy kittens out of cats who have tested negative for FeLV & FIV. If the kittens were treated for URI (Upper resp. infection) buy from someone else. A well kitten who had a course of a URI will be fine as a pet, but if it happened to have herpes, & you buy it as a breeder kitten. All your kittens will get sick when they are 5 to 6 weeks old.
I wanted NFC's in 2001. Without experience, no one in the USA wanted to sell me a breedable one. They wanted me to buy a casterated tom cat. Show that, and then if things went ok (if they liked me) they might sell me a breedable kitten some day. I've been around too long for that sort of BS.
So we ended up with a pair of Ragdolls, discovered we could import NFC's, so started with 2 breeds. The Ragdolls were nothing but trouble. Massive amounts of money spent on breedable kittens who would not, could not, or would allow nothing to breed them. One cat probably had herpes, as she made all her kids sick. All 8 of them. Cost me $800 in vet bills to get the litter well, and keep it that way. We did not continue breeding Ragdolls.
Fortunately the NFC's are healthier, or possibly I was lucky enough to get healthier cats to begin with. The biggest problems have been queens who really weren't made for breeding. 2 had their kittens too late, & needed c-sections if I wanted live kittens. Both were spayed and petted out. Another wanted to lay on her side & not allow a male to breed her. She was so pretty, I had a show title on her already, but went ahead & petted her out. Another never had enough milk. I got tired of bottle feeding kittens in the middle of the night, so petted her out also. She had such gorgeous kittens.
If you purchase 4 to 6 breedable kittens, you can spend $30,000 the first year. That is the price of the cats. Initial vet bills includeing tests for whatever you are worried about. Setting up living quarters for a couple toms. Buying kittening cages & setting them up the way you want them. Other equipement you will need, maintaining cats in good condition, going to a few shows. Queens are pretty easy, they can just run around the house. You wouldn't need a kittening cage, if you have a room you can lock a soon to be mother in. If you don't your cat will do things like have kittens in the closet, under the bed, on top the bed, under the recliner, in the bookcase, etc. etc.
Raiseing kittens is a little more complicated then you would think.