I don’t know how to be happy?

This is exactly what I tell students. If you feel a pall come over you on Sunday when you realize that you have to go to work on Monday, regardless of what they pay you, this is not the job for you. Somewhere out there is a job that will make you feel fulfilled. It might help to consult a career counselor- there are tests that can show what you'd be happy doing. But the happiest people I know are the ones who have the least time to worry about whether they're happy! They have families, friends, activities, jobs- full lives.

Try helping other people. Don't change anything else for now, but add some volunteer work to your schedule. In addition, find people you know personally who need help. This doesn't have to be a big deal; you can help in small ways.

Help an elderly neighbor or relative weed their garden or shovel snow; Offer to walk their dog or clean their house. Visit someone who is lonely. Offer to babysit for a parent who is stressed. Write a letter to your grandmother.

Do what makes sense for you, but do it often, and regularly.

Make these changes regularly for six months, and see whether you feel differently.