Is drewn an english word? Can we use it as a past participle of draw?
It needs to be understood that words arrived in the English language through about a hundred different paths — starting from Latin, French, Italian, Spanish, German, Dutch, Scandinavian, Scottish, or Irish, then often ping-ponging back and forth between Old English dialects, and merging and re-merging with said dialects. While one can often discern patterns as to how, eg, verbs are “declined”, there are few true “rules” — some verbs fit the patterns very closely, others not so well. Given the nature of how English developed there is nothing remarkable about this.
Directly addressing the question: “Drawed” is a moderately common, though erroneous (per most authorities) past tense of “draw”. (“Drew” is the correct past tense, and “drawn” is the past participle.) I’ve never heard/read “drewn”. If you look in an “authoritative” online dictionary such as Cambridge it will list these.