Call me stupid, but I'm only 11, what are contributions?
"Contributions" are generally sharing what you know about the hobby - helping others with problems - asking questions, generally being a helpful nice person. It's not a clearly defined "quality".
Your age generally doesn't come into play in these forums - except that many of us "old fogies" can sometimes lapse into outmoded speach and make archaic references to things and happenings from decades past.
Of course, noting that you like decent aircraft - like Vimys and such shows that your are mature beyond your years and have excellent taste.