a)
The award is for a person who makes a difference in people's lives, through organising developing projects or showing leadership skills. Anyone can nominate a candidate.
b)
He welcomes immigrants at a refugee centre in Australia, helps them with the language and with forms and documents, helps them find apartments and jobs and provides moral and sometimes financial support. Personal qualities: humble, has dignity and kindness.
c)
- goes under the radar.
- has made a huge difference to people's lives.
- has worked tirelessly.
- provides moral support.
- is an example to us all.
- must have helped thousands of people.
- would be a worthy winner.
- Idiom → Go under the radar means not to be seen or known by many people.