ICAO CPL H to FAA CPL H

[ersa]

Hi guys,

I'm looking at converting an icao CPL h to faa CPL h.

what I would,like to know is

1 best way to pass FAA CPLH theory test, is there a book I can buy and simply revise the info or website I can buy access to to study.

Do I need a sign off from an FAA instructor to sit the test or simply rock up to an FAA testing centre or book on line ?.

I have CPL licences Issued everywhere but FAA .

Any advice please