Free online schools/programs in the uk?

im 13 and having anxiety because of school , I dont fit in with the other students and the teachers pick on me because im quiet . im hardly ever relaxed in the class room and feel much happier at home . my mum said she would let me homeschool but she doesnt w ant to pay and is worried about me getting GCSEs ( I hope to do animal courses at college/zoos so I can train to be a vet ) please can I have some advice and some free online schools ? thanks