The previous responses are both good advice. We have a 9 month old puppy that is dealing with the same issue. One thing that is helping us is tandem walking. If you’re not familiar with the concept, check U-tube. Basically you are walking your dog behind, along side of, and ahead of another dog. Reward when their behavior is appropriate. Increase distance if you can’t hold their attention. If you can’t recruit a friend, pirate other dog walkers at nearby parks, by following close and passing wide when you can.