Teach them a Watch Me, do this randomly throughout the day. Start where there are no distractions, and your dog isn’t doing something else. Say their name enthusiastically and when they look at you reward them with a high value treat. Once they can do this reliably, practise this everywhere – always rewarding them.
Avoid places with many dogs, start training your dog the Watch Me exercise in a quiet place indoors where it’s just the two of you. Once you can do this at home, you can progress to the garden where there are more distractions from sights, sounds, and smells.
Distract them when meeting other dogs, start off a long distance from them – beyond the point where your dog would usually react. All you want your dog to do is look at you, and you will reward this. Slowly build this up to being able to do it at closer proximity but never too close that your dog feels that they need to react to the other dog. Always use high value treats to reward them for paying attention to you and not the other dog.
Practice is key, remember that patience is very important when training any dog and you shouldn’t expect instant results. If your dog has been barking at other dogs or being reactive for a long time, it will take time, patience, and consistency to break the habit or change the behaviour.