>>534971102
Look up gesture drawing, this is the exercise you need to do to be able to draw the human body. Then check out something like hide channel on Youtube for anime figure drawing specifically. After that you can look up an artist you like and copy the way they draw the face and their coloring to learn from it.
If you're at the stage where you can't even draw a 3D cube yet, consider doing something like Drawabox to develop your spational reasoning and learn to draw 3D objects.