You've made several spelling mistakes, actually (lol assments).
Well while it could be argued that it depends on what you want to do in A Levels and the future etc etc, English and Maths are the most essential for a lot of courses and a lot of jobs. They just confirm that you have a basic understanding of the subject.
It could come back to bite you, think of resitting it now or in the future. My friend is a good example. He wanted to apply to an Architecture course in university, he would be great at it but it requires a B in Maths which he doesn't have so now he's had to go with something else.
GCSEs don't really matter all that much though Maths and English, as I said, just demonstrate a basic understaning that courses and employers like you to have.
EDIT: I took so long to type this up, I just saw you say you want to do plumbing. I could be wrong but I believe that requires an understanding of Maths.
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