안녕하세요 : Hello! (formal) 만나서 반갑습니다 : Nice to meet you! (formal) 안녕 : Hello! (Lower) 만나서 반가워 : Nice to meet you! (lower)

Formal tone : You usually use Formal tone (존댓말) to someone who's older than you, not very close with you, or is partners in business such as upperclassmen. Lower tone : You use 반말 to the ones who are close with you such as friends, someone who's younger than you.

the way to pronounce can be found here >>

in 안녕, you may see there are something under 아 and 녀. they are called 받침, and the 받침s are always pronounced later.

Read what's on the top first, then the bottom case letters. The Vowel and the Consonants ALWAYS goes together when writing Hangul.