The only thing you need to so to charge $700 an hour is convince a business your services are worth that much, typically by saying that in X time you can delive

The only thing you need to so to charge $700 an hour is convince a business your services are worth that much, typically by saying that in X time you can deliver Y result which will increase revenue or decrease costs by some number Z, where Z is greater than your rate times X. There exist at least some software developers who bill $700 an hour or north of that, by the way.