Read the info at the links given, most of what you need is there. I understand not everyone knows the layout of an RPGMaker game though: most of the text (dialog, item names and descriptions etc) is stored in various text files in the data folder. It can be a lot to dig through in raw text though, which again is why I recommend Translator++: you just point it at the directory and it should be able to figure everything out on its own and load things up. If you have specific questions, feel free to ask though.