Well for starters it’s "clear your mask", you clean your mask with toothpaste as needed and wash it with watered down baby shampoo before each dive.
Now how is your mask flooding, is the water leaking in or did you let it in for the clearing drill?
Hold the top of the mask against your forehead, tilt your head back about 45 degrees and exhale slowly. Your tub is not deep enough to have your head at the right tilt and the water goes up your mask! If you blow too hard your exhale will exit the mask too. Being new your are rushing the process because you are anxious to breathe again.