How do you get free breakfast at Hilton hotels in gold status?

The reservation desk agent will give you coupon for free breakfast at the hotel or you should see the free breakfast option when booking the room online?

Is the breakfast free at all hilton hotels around the world for gold member?

I have hilton gold status but no hilton cards.
I have vacation coming up in BANGKOK and might stay for about a week at the conrad hilton or the millenium there.

thanks