Few thoughts.
Our working cocker has been a dream to train. He is the least strong willed dog that I have ever met
Our Springer is far more stubborn.
I would have your puppy off lead immediately, from the first walk. They will be too scared to go more than a few feet away from you, honest.
Ours has a docked tail, I also don't think its a bad thing. Saying that, he has at least 2/3rds of his tail intact, not a little stump. I think that's common these days.
I just personally wouldn't run with my spaniels. I again, personally use the time spent walking to train as well. So, lots of waits, recall, sniffing out treats, down stays, scent trails etc. They are focussed on me then, not other distractions.
I think you would definitely need more that vet based training classes.
Have a look into the KC Good Citizen Awards. They have a bronze, silver and gold award. We did these with ours, you end up with a well mannered, well trained dog if you put the work in.
Also, clicker training is great fun and spaniels do respond well to any kind of training. Google clicker training or search it on YouTube. Kikopup is a good place to start, but there are many others.
Our cocker was a dream, but in fairness to other comments above, I have known folk really struggle too.