It is a 3rd degree felony. He will be looking at a minimum of 2 years and a maximum on 10 years in prison and up to a $4,000.00 fine.
Your marriage will not automatically dissolve. I would talk with an attorney that handles family law about the other legal questions that you asked.
I agree with the other attorney that answered.
Neither marriage automatically "dissolves". The second could actually become valid if the first marriage ends for some reason - divorce or death of the first wife. It is complicated so I suggest that you consult with an experienced family law attorney in person.
Since bigamy is a crime it is up to the district attorney to file charges against him. It's not up to you to handle this matter.