Welcome to the fanatics forum .
From your post it seems you are technically challenged and your mechanic is mentally challenged .
My advice is get another mechanic .
Normally a head gasket blows and a car overheats . The amount of damage will determine what has to be fixed .
If you rode the car till it stopped you may have terminal damage with replacement or engineering work needing to be done . Your mechanic should see this if he stripped the head off , then he can advise youu what to do .
You could have your car taken to Gizmo here on the forum . You can phone Warren on 0832540344 .
Good luck .