The most common Korean word for “hot” is 덥다 (deopda). There is one more word with a similar meaning — compare them below. 「hot」는 한국어로 덥다.
to be hot (weather)
TOPIK 1 · adjective
Words and levels: TOPIK I essentials (National Institute of Korean Language standard curriculum, KOGL Type 1) · examples: Cheesepotato