Show that 0^n1^n is decidable
If a language decidable by a PDA then it is also decidable by a TM. In other words TM are more computationally powerful than PDA, i.e., the class of languages decidable by PDA is a proper subclass of the class of languages decidable by TM. You can also easily simulate a PDA on a TM.

However not all languages are decidable by PDA. So your approach does not work in general.

As to CFG to PDA conversion I would recommend the textbook by Sipser (pg 116). Google search for "CFG to PDA" also gives a good result.