Can't get resources on minecraft pocket edition?

You need to craft a wooden pickaxe in order to obtain the cobblestone first. After you craft the wooden pickaxe, you will be able to break the cobblestone faster and obtain it.

Chop a tree, mine it with a woodenpick axe, from there you can make a stone pick, iron, then diamond.

To get cobblestone you must break it with at least a wooden pickaxe, which is made with sticks. Sticks are made from planks. Planks are made from logs. Logs make trees and trees you can harvest with your fist.

Yes you need a pickaxe to get cobble.

Ok, i'll try and not make this complicated.To break stone you need to have a wooden pickaxe.Pretty much how it goes is like this
Wood can break Cobblestone.
Stone can break iron.
Iron can break Diamond, Redstone and Lapiz.
Diamond can break everything apart from bedrock.
Second, I recommend you read a guide on the internet on how to play.IT IS MAJOR Help.Otherwise you'll just be running around like an idiot.