The usual route into physiotherapy is by obtaining 5 GCSEs (A-C grades, to include English, Maths and science subjects) + 3 A-levels (A-C grades, to include Biology) and then taking a full-time degree course.
http://www.learndirect-advice.co.uk/helpwithyourcareer/j obprofiles/profiles/profile435/
Some people start as an assistant physiotherapist and then take a part-time degree course. The minimum requirements to train as an assistant physiotherapist are 4 GCSEs (A-C, including English, Maths and a science).
http://www.learndirect-advice.co.uk/helpwithyourcareer/j obprofiles/profiles/profile1271/
Chris