I want to have an image showing in the main menu.

Now what would the code look like, if I wanted to do such thing?

 

Any ideas(please be specific)?

Hook into GuiScreenEvent.DrawScreenEvent.Pre or Post.

Check instance of current (inside event - accessing via event.gui) GuiScreen (for main menu its GuiMainMenu).

Draw your stuff, remember you are in Pre or post of main drawing, so all GL states are inherited.

Use Gui.drawTexturedModalRect to draw .png file as ResourceLocation.

Can you make a sample code of this for me please? I am.. not even a beginner.. I just don't understand everything..

Could you do this for me please?

The code I mean..

Not to be unhelpful or anything, but this forum is for Forge, it's not Java school, so I strongly suggest learning that 1st.

 

As to code - I don't think anybody will write it for you. Base sample:

Register event class in client proxy (gui is for client only obviously).

MinecraftForge.EVENT_BUS.register(new ClientForgeEventClass());

@SubscribeEvent
public void onScreenDrawing(DrawScreenEvent.Post event)
{
    if (event.gui instanceof GuiMainMenu)
    {
        // Do your stuff.
    }
}