Hi
To answer your question, you will not be able to do the theory here, and the flying in Brazil.
Refer to Lasors 2005 on the CAA website
www.srg.caa.co.uk and read section C1. (PPL requirements).
What might be easier is to get a Brazilian PPL issued, come back to do the 7 JAR PPL exams, and a skills test to get a JAR PPL issued on the basis of you Brazilian ppl.
If you have any more questions feel free to ask me.
v