one / won are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
one: (noun) the smallest whole number or a numeral representing this number. (noun) a single person or thing. (adjective) used of a single unit or thing; not two or more. (adjective) having the indivisible character of a unit. (adjective) of the same kind or quality. (adjective) used informally as an intensifier. (adjective) indefinite in time or position. (adjective) being a single entity made by combining separate components.
won: (adjective) not subject to defeat.
one: w·AH·n
won: w·AH·n
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)