Things to research:
Size - do you know how big a fully grown adult is, will your house & garden be big enough?
Activity levels required - physical and mental. How much walking and how often? Will you be able to do that or will you need a daily dog walker? Can you afford a daily dog walker? What do they need mentally? Will the become destructive if bored/ left alone?
Health - what health problems is the breed probe to? How much do these cost to treat with a vet? How much would pet insurance be for this breed? Can you afford it? How much would treatment be without insurance? Could you afford it? Bear in mind all pure breeds will have specific health issues due to the selective breeding & small gene pool, so chances are your dog WILL have medical issues specific to the breed at some point, as well as normal day to day dog health probs.
Breeding - where are you going to get one? Puppy farms are NOT OKAY and you will be responsible for animal cruelty if you buy from one. Most ads on gumtree, find a pup etc are puppy farms and back yard breeders - research these so you know what you're getting into. If not those, you will need to find a reputable breeder who may not sell to you if they judge you don't know how to look after the animal properly.
Family dynamic - what are they like with kids? I vaguely recall something about them liking to herd children; basically pushing them into a group together where the dog thinks they ought to be, which is probably fine for older kids but not great if you have little ones.
Grooming and cleaning - anything with that much hair is going to require hours of grooming per week. Find out how many. Can you commit to that. If not, how much would a groomer charge? Can you afford it? Then find out about moulting. How much extra cleaning of your house will be created? Do you have time? Can you afford a cleaner if not?
There will be web pages specific to the breed with all this info. Get googling, get reading.