My dog had a crazy high prey drive as well. We started with training in the home (no distractions), saying “look at me” and when he looks and holds eye contact, he gets a treat. Then medium distraction (our backyard where we seldom see squirrels or much else) and doing the same thing. And then on walks, as soon as his ears perk up at a squirrel in the distance, start doing look at me and give lots of treats so he mostly forgets about the squirrel. Must use a very enticing treat for this like chicken not just training treats.

The goal is to train them so that when they notice something, they look at you instead of wanting to chase the animal.

And it definitely takes a long time! He’s not perfect yet but he’s much improved.