Although they are a bit more expensive, I prefer a 6’ leather leash for older or adult dogs. I’m not a fan of nylon leashes for older stronger dogs, especially the thin and narrow varieties.
For a brand new puppy you may want to start with a nylon leash though with a small clip that hooks onto the collar as they are less likely to bump into a young dog’s face. A 4’ leash is a minimum, 6’ would be better.