Will only Move in reverse

My husband put it in four wheel drive high. After I noticed I changed it to two wheel drive when I was still driving. While I waited at a stop light when the light turned green I tried to drive and it would not drive. When I put it in reverse it reversed with out an issue. When I put it in low gear one it kicks then reverses. I noticed that the transmission fluid was empty so I put one gallon and two quarts of transmission fluid. It still did not want to drive it will only let me reverse. My dash is not giving me any warning issue's. The engine starts with out any issues. It revs up on drive but will not go forward. What would cause this issue?