Two things:

1. You got a working dog. A terrier is DESIGNED to be a ratter. His job that he wants to do 1000 hours a day, constantly, every single day, is to dig and chase and pursue tiny little furry things. And kill them.

2. You need professional help. A dedicated trainer and obedience classes. Probably 3x/week for the first two months, or so, then weekly for 6-8 months.

Sorry for the bad news. You got the wrong kind of dog, basically. You got a highly active working dog that is genetically predisposed to ACTION. Constant action.

What will happen when you go to training/obedience class, is that YOU will be trained on how to deal with your dog and it's inherent design. You will get better at communicating with the dog. You will understand your dog's motivations, and how to guide your dog's behavior. But you will never be in control. This dog is, and will be, your alpha, and you will always be subservient to it.

Again, sorry for the bummer. But I have three friends who deal specifically with "difficult dogs", and this pattern repeats over and over and over and over. When you walk into the pet obedience school, the owner of the place will see you and the dog and already know everything you have said here. And much more.

Good on ya for adopting. But next time, go with a dog the size of a couch. They are designed to chill and hang out (Golden Retriever, Labs, etc.), and go for occasional walks. There is a reason why service dogs are always retrievers, labs, and beagles.