In a essay question if you state points which are not on the mark scheme but fully relevant to the question would the examiner still award the marks?
Usually, yes. Essay markschemes usually don't list all relevant points that could be stated. On the markscheme does it say something like "Any other valid points with reasoning"? Even if it doesn't say that it most likely will apply.
Yes, for English it normally says "Suggested content", but then it says something like "all relevant examples with evidence should be awarded credit. So it should be fine.