Posted by Loyd Grossman is Miss Venezuela (41 days ago)
If you are entitled to a UK passport and you were born in the UK, I think you just need your original birth certificate. You also need to to get a British or Commonwealth citizen of good standing (who you have know for 2 years) to state on your photo that this a 'true likeness'. This is quite hard now as a lot of 'good standing' Brits, Aussies and Canadians have now left.
(I am based in Hong Kong)