Will or be going to

My hands are dirty. I am going to/ will wash them.

That bag looks heavy. I will/am going to carry it for you.

Look at the sky! It will/is going to rain

That call is sure for me. I will/ am going to get it

Why did you buy that paint? - Cause I will/ am going to paint my room.

Look at that boy on the edge of the roof. He is going to/ will fall