I agree with PK, if you start on a martingale now, and do not let your dog dictate your walks she should develop some great walking skills and habits now while she is young. she should follow your lead and walk, and stop when you stop. She should be behind or beside you all the time. You should never let her walk tight against the end of the leash, ever. she should walk beside or behind you without tugging. I made the mistake of letting my dog dictate where we went, I dint care how far we got we were out for an hour. Now I realize how bad a habit that was. He needs structured walks and needs to know I make the decisions and not him. It will take a little while to get your dog on board walking properly, but it will be so worth it in the end.
“When you KNOW better you DO better.”
― Maya Angelou