you should live to bring glory to God who gave you life and share His love the world.
it is neither to just exist or just fulfill your own sense of "fun"
sometimes you will be miserable but if you have God's love in your heart, you will have joy in your heart no matter if you are beaten or rejected by the world because you should live life for a higher calling and a higher purpose.
Ephesians 2:10
For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand that we should walk in them.