Here is a short list of frequently encountered false cognates from Spanish to English you should be familiar with when conversing with native Spanish speakers:
Pie – In Spanish, this word means “foot" but in English it’s a type of pastry baked with a fruit filling.
Assist – In Spanish, this means “to attend" or “to be physically present." In English, though, it means “to help" or “to provide assistance."
Contest – In Spanish, this is a form of the verb “contestar," which means “to answer" or “to respond" rather than the English language meaning of “a competition."
Fume – The verb “fumar" means “to smoke" in Spanish, a far cry from the English meaning of “vapor" or “gas."
Libreria – Not a “library" or “a place to store and read books" as in English, rather, it’s a place to buy books or a book store.
Mayor – Another frequently encountered term which can cause confusion, in Spanish, it refers to being “older in age" or “wholesale" in business versus retail while the English meaning is that of the title of the head official in a municipal government.
Sin – In Spanish, “without" is the most common meaning of this false cognate while it refers to “wrongdoing" in English.
Tarjeta – A reference to a small card like an ID card, bank card or credit card, it’s nonetheless quite similar to the English word “target," “an object of focus", with which it is often confused. Although the words are spelled a bit differently, their pronunciation in Latin American Spanish is virtually the same.
Recognize – This is the verb “reconocer" in Spanish, which means “to admit" as in “admit an error." The English word “recognize" has reference to “making an identification" or “to identify."