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By the way, im 10 and already have a coin museum and around 290 coins."
-that's a pretty impressive collection & quite the accomplishment to have a coin museum. Way to go!
A
video I made a while ago shows the basics for CDN banknotes on my
Notaphilyc Culture site. Take circulated banknotes, hold them up to a strong light and start to practice examining them once you have an understanding of the basics terms. Be ruthlessly critical of each note's most minor imperfections. Once you've developed a strict conservative eye than you'll have no problem determining a banknote's grade down the road.
Hope this helps & good luck.