Some options from a thesaurus (some better than others): peanuts, crumbs, chicken feed, chump change, nickels and dimes, pittance, small potatoes, scraps, drop in the ocean, trifle.
Of these, "peanuts" and "small potatoes" are probably the ones closest to appropriate in your sentences.
The closest thing I can think of to what you are aiming at is
Fake it till you make it.
It means to act like whatever you want to become until you actually achieve that quality.
That does involve a certain amount of deception, but your definition includes someone not having an ability but being perceived as having it, which is deception whether or not the intent is to deceive.
Best Answer
would be appropriate. From Oxford Dictionaries: