“Sometimes the questions are complicated and the answers are simple.” - Dr. Seuss quote
You don't have to figure everything out before you take a step. His agreement is not necessary. You only need to do one thing right now. There is only one small step to take.
Go talk to a lawyer.
Then you will find out what the next step is. Then do that. And then the next step will be clear. Do that thing - and on and on.
Your lawyer will help you determine the next step and how to make that happen. You can do this without uttering one more word to your husband. The lawyers and the courts will work out the details. They will get your equity.