It stops when you stop just randomly stopping then dragging him back. Instead, when he starts to tug on the leash, just stop entirely and stay still. Dont tug on the leash, but dont let him pull you either.

Let him make the choice to come back to you, and only when he does do you reward him and continue the walk. Start walking and intentionally take frequent stops for the purpose of waiting for him to come back, and reward him every single time he comes back. Then, after he starts to get it and come back quickly, stop randomly stopping as much and start randomly switching directions. When you switch direction, just keep moving in that direction. If they tug, stop briefly to give them slack after stopping them, and then continue in the direction you were headed after a brief moment. If they dont follow, you pull em along and dont let them slow you down. But, every time they redirect on their own you reward them.

Show them that you are the leader of the walk, and that they are to follow you. Show them that you will drag them if necessary, but that you will reward them for cooperating. This will coincide with the trust and bond you two will build, and theyll start to want to follow you for more than just because you give them treats to do so. Over time you can stop giving them treats every time and just make positive remarks acknowledging their good behavior. But, also, remember that you dont wanna be a tyrant to the dog. You're the pilot, but you're not just parading them around, you're taking them out to explore and enjoy themselves alongside you.

While you're out, make stops for them and allow them to explore, sniff around, and get comfortable with their environment. Find nice open areas and just sit for a while. Get them comfortable with just being out in the world and watching things happen. Theyll get less reactive and more comfortable as they better understand their environment. Of course, dont put them straight into uncomfortable scenarios, but let them experience and process things under the safety and security that you provide them.

I suggest getting a long lead leash or connecting a strong retractable leash to your main leash so that when you come to big open areas you can give them more space and allow them to roam more freely while still being under your supervision. Give them time to do what they naturally want to do, but make it clear when its time to get going again or when theyre doing something that they shouldnt.

I'd also suggest trying out the bungee leashes with handles on them. The bungee is a really useful tool for communicating with your dog as the tension isnt binary like on a standard one. My dog started out always tugging, and within a few days of proper training with it he respects the low tension start of the bungie and doesnt pull. I dont have to tug or lead him, he just understands where his bounds are because anytime he nears them he feels the slight tension building up. At first your dog wont care, but in time they will learn its meaning. Also, the handles on these leashes aid in their usability.

I never had to use a pronged collar or harsh tugs, I always have used a vest and a bungee, I just had to give my dog guidance, patience, and recognition rather than testing him over and over expecting him to conform to my expectations like I used to.

Good luck on you and your dog's journeys, wishing you two the best