Potty and crate training questions

Hi! So my puppy is approximately 6 weeks old, he still doesn't know how to go up and down stairs and he can't because his limbs are still too short to do so, he's been puppy pad trained since I needed to check his poops and pees to verify that there weren't any parasites in it, I keep reading stuff about crate training him and getting him to go potty outside but I don't understand how those two relate?, as soon as he's able to go up and down the stairs on his own I want to start training him on how to go potty outside, but I want to verify with other puppy owners that this is not like something that will permanently make him unable of understanding where to pee and poo, also he sleeps on his own bed in my room.

A lot of advice I find on the internet is for Americans with American homes in mind, in Mexico i've never heard of crate training even though I've asked one of my teachers which is a veterinarian and a dog training specialist, a bit of more information about it's usefulness would help a lot.