They mean you need to learn to walk before you can run. In other words learn how to hook directx functions first there are plenty of tutorials on how to do this, search vtable hooking. Just working off someones base will keep bringing you back here asking how to do basic things like display text on a screen.
Instead of pasting code i will help you by saying you need to create your font (D3DXCreateFont) in endscene or present ,which are directx functions. Then reset your font when the device resets ( Font->OnResetDevice() ) , or at least thats how it was awhile back not sure if that is still necessary.