I would use an already existing song and then sing the lyrics along with the
song. Then add words. It´s really easy to do it like that and after a while it
will feel like a fun puzzle.
I found an acoustic version of the song and used your lyrics to sing
along to it. I used the phrase "True love is the key" as a chorus.
The song could be called "True love"
Original song "Bite me" by Enhypen.
It's you and me in this world,
=Open up your heart
내게로 다시 와, tie me
=listen to the melody
날 구원할 거라면, just come kiss me
=It is with the soul
and bite me (oh, babe
=True love is the key