if some one could help me out on this i will be happy

How to :

Make a sprite appear on a key press. The sprite needs to fade in.

Make a sphere model be filled with myst.

Codes i will like but pointing me in the good direction or to
the right AUM will help me also.

key press functions are on_f1, on_x etc.
also you can check if key pressed on the current frame with an if(key_x)

to fade in the sprite, set it's alpha to 0, the in a loop, sprite.alpha += 10*time_step;