So the Korean alphabet is something i struggled with when i first learned Korean, for it is very different from English- it has characters and not letters.
The Korean alphabet is called Hangul. In order to remember these, you must practice reading them daily. Of course depending on the position the character is in it can change its sound, but stays similarly close to its original.
It shows both Hangul, Romanization, and English. in order to learn, if you speak english, use romanization to get the jist of what they(characters) sound like.
안녕! an-nyeong! bye! i hope this helped