I dont think this is a good question because how do you think bitcoin can help poor countries do you really think that bitcoins can help them grow if they dont have money for food how would they have money for bitcoins lol.
I think the people that have nothing to eat is out of the equation. It's only common sense that they can't afford a computer or a smartphone to do bitcoins.
It's not mandatory that you buy bitcoins at first. You can earn them for free from signature campaigns, and faucets although both would take some time. You can also offer services and sell goods. I came from a poor country and I say that bitcoins have helped me and most of my friends online to buy things that we can't buy before. Some of them have started their own business in real life and some are still saving enough bitcoins.