Well since im new to forge modding, and objected programming (not programming itself). I've got question, how to make block using energy? and producing energy one.

 

GLHF take care

With capabilities. You can also look at an unofficial version here. Either or, a block does not create energy nor produce it, it is just the container for the TileEntity that handles the dynamic data. From there, you can look at the methods and see which one inserts and which one extracts energy from the object. Do not forget to read and write the data and invalidate it in their appropriate methods. You can use one of the existing TileEntity classes (e.g. ChestTileEntity) to see how to handle that.