Most successful female models are over 5' 8" and measure 34b,24,34 or thereabouts.
Most male models are over 6 feet tall.
Measure yourself. If you are nowhere near these measurements there is little chance that you will succeed in mainstream fashion and photographic modelling.
Teenagers do not need to conform to these measurements!
The glamour and adult entertainment sectors also have rather more flexible requirements !
Top editorial/fashion models
The most glamourous jobs (including campaigns, the collections and magazine editorials) are reserved for the top editorial/fashion models.
This work is very eagerly sought after by fashion models because of the exposure it provides. For this reason you can expect to work long and hard for just £100-£300 a day but you will get tear sheets for your portfolio that will help you get work.
Commercial Print Modelling
This refers to when models are photographed to promote a product on billboards, buses, magazines and newspapers. This type of modelling can be divided into two sections: Fashion Advertising and Product Advertising.
Catalogue modelling often provides regular work and pay is generous (£100-250./hr or up to £2500./day.)
Runway or Catwalk Modelling
This is one of the most effective ways to gain exposure and is considered the most glamorous type of live modelling.
Glamour and Adult Entertainment
Glamour modelling, swimwear and lingerie often involves some nudity and sexual posing.
Adult entertainment modelling and acting requires nudity and the performance of (or simulation of) sexual acts.