I want to travel all over and volunteer to help those in need. Im thinking like Africa and South America. My church does not do mission trips.

Hi guys,
I am from Malaysia, I plan to travel from London and visit Europe by train. Our currency in Malaysia is 6 time smaller then euro. So i need to work if I am to travel in Europe, can anybody help me with my question? I’ll be holding a visit visa, but would it allow me to work and travel as I visit from one town to an other?