Pronunciation: [am ɐ fˈɔ͡ɪl tuː] (IPA) 
The spelling of the phrase "am a foil to" is fairly straightforward. "Am" is spelled as it sounds, [æm], with the "a" pronounced as the short "a" sound. "Foil" is spelled as [fɔil], with the "oi" pronounced as the diphthong [ɔɪ]. Finally, "to" is spelled as [tu], with the "o" pronounced as a short "o" sound. Together, the phrase means being an opposite or contrasting character to someone or something else.
To be "a foil to" someone or something means to serve as a contrasting or complementary element or character that highlights the qualities, attributes, or actions of the other person or thing. The term "foil" in this context originates from the practice in literature, particularly in drama, where a character referred to as the "foil" acts as a contrasting character to highlight certain aspects of the main character.
When someone is described as "a foil to" another individual, they typically possess characteristics or qualities that are different from or opposite to those of the person they are being contrasted with. This contrast often serves to emphasize specific traits, strengths, or weaknesses of the main person or thing.
The person who acts as a foil is usually employed to enhance or showcase the qualities of the other person or thing, providing a clearer understanding of their nature, characteristics, or actions. By being different or opposite, the "foil" adds depth and complexity to the main person or thing by placing them in a different light or perspective.
Overall, being "a foil to" someone means serving as a contrasting or complementary counterpart who allows a better understanding or appreciation of certain qualities, characteristics, or actions, thereby enhancing the overall narrative, interpretation, or portrayal of the main person or thing.
