Driving the van starts slowing down to a complete stop. Then it will not forward

This will require a complete inspection of the brakes. We need to know if one or all calipers are clamping down. Also have you inspected the parking brake? This could be a collapsing hose, bad caliper, water in the brake fluid, etc. Here is a link to find a shop near you . https://repairpal.com/repair-shops Alex