Present Simple is used to express facts and Present Continuous is used to express processes.
We use Present Simple when we are talking about:
actions or things that happen regularly:
She does not eat a lot of bread in the morning.
He always does his homework in the evening.
states
They do not like juice.
Do you want a little ice-cream?
Present Continuous is used to express:
actions that continue during the moment of speaking
I can not go out. I am doing my homework.
What are you doing right now?
actions that take place in a certain period of time
I am reading three books in the moment.
He is not living at home while he is at university.