What is your reaction to someone who aspires to be a flying examiner -FE, but who has never been a flying instructor - FI ?
Nothing wrong with aspiring however, if you haven't been an instructor what would you know about students or examining?
For that reason Examiners are required to meet minimum instructional experience requirements, and share the respect of the aviation industry. Without either of those you will not get an authorisation.
Your question, if serious, displays a degree of naivety that would not stand you in good stead as an examiner!