5 steps for reliable loose lead walking [These steps are identical for an 8-week-old puppy or re-training an adult dog]
Do NOT even think of taking your dog for a street walk around the neighbourhood until s/he knows HOW properly to go for a walk.
What does 'properly' mean? It means never pulling, not even for one step, and always walking with a J bend in the lead at all times.
If your adolescent/adult dog has trained you then you need to go back to kindergarten & start again, as in 1-5 above