1991 Cutlass Calais. Rough shifting. Will not move ,, not even into neutral?

Hello, it sounds like it may be possible that your transmission may have an internal mechanical concern, resulting in the stall. Only hands on evaluation can be helpful.

Could be a transmission failure, a total loss of fluid, gear shifter linkage issue. Hands-on inspection is needed. Use this link to find a good shop near you. https://repairpal.com/repair-shops Alex