The most common Korean word for “most” is 가장 (gajang). There are 2 more words with a similar meaning — compare them below. 「most」는 한국어로 가장.
head of a household
TOPIK 1 · noun
most; majority
TOPIK 2 · noun
Words and levels: TOPIK I essentials (National Institute of Korean Language standard curriculum, KOGL Type 1) · examples: Cheesepotato