I have a rescue Border Collie, the 8th one over 40 odd years. He has a lovely nature with us and other people but he is scarred by his bad first 3 years. Collies do tend to develop quirks from fear in their past and being too inteligent so need to occupy their minds. Ours was dreadful on lead when he first came to us, he would get hysterical when he saw another dog and would spin all the time. We use a half choke collar with an extension lead, or in order to catch him, even in our garden a slip lead. After 5 years he is much better and safer on a lead but will still not go through a door if you stand by it or be caught by his collar.
My OH took him to dog training and it really did help the dogs confidence and help with getting him to walk better on a lead, plus the socialising with other dogs worked so he is now ok with other dogs. After 5 years we are just about getting a reliable recall, but can not let him off the lead on walks, he he too much of a risk. Fortunately he can run in our own field and large garden.
So it will take time and loads of patience, but it is so worthwhile, he will improve.