How do I get to work in a Radio station?

Are there any Canadian development projects in Madagascar? If yes, you could contact them to offer your services as a trainer for radio equipment. But the chance to be employed by the Malagasy radio broadcasters is close to zero, and if it was better, you would never be able to make a living with this.

As a video professional I worked as a trainer for "Expression audiovisuelle" at a journalist school in 2004 and also held a training course for brandnew equipment sponsored by the German government for the former TVM studios in Tana. The participants were superhappy with the new equipment and the course which I held partially in Malagasy - but unfortunately the whole studios incl. the brandnew equipment were set on fire a few months later in the course of the "unconstitutional change of government"...

Better found a school for radio and audio technology and operation and train young Malagasy people to help them develop their professional knowledge!  Good luck!