This is gonna be complicated. But I'll try to give you the easiest way possible.

Learn how to read (Case 1):

Consonant + Vowel = CV

Examples:

ㅊ(C)→ㅏ(V) = 차 (CV)

차 means "tea"

ㅇ(silent C)→ㅑ(V) = 야 (CV)

야 is a very informal word that means "hey!"

ㄷ(C) →ㅓ(V) = 더 (CV)

더 means "more"

ㄱ(C) →ㅏ(V) = 가 (CV)

가 means "go"

ㄴ(C) →ㅓ(V) = 너 (CV)

너 is an informal word that means "you"

only use informal words to your close friends or those who are younger than you.