In Language Portuguese :

Na minha empresa, fizeram um BO sem o metodo FillAllGl(). Como eu faço um BO com o metodo FillAllGl e como editar esse BO ?

You just open the code for your BO, either right-clik on it on the Solution Explorer and choose View Code or on the designer click the "click here to switch to code view", and then you will find a Region (Data Retrieval Methods) already created for you to type in your Fill methods.

Have a look at the help file and you can find examples of how to do it. Also, it would be a good idea to open the StrataFlix sample and have a look at how things are accomplished.