".... and being proud is the most reliable source of happiness that I know."[https://tim.blog/2018/02/03/the-tim-ferriss-show-transcripts...]
Teach yourself how to cook, get in shape, draw a picture, write a story, help someone less fortunate, teach someone something you know, learn how to juggle... In the end it doesn't really matter what it is but you will have that proud feeling and be happy in that moment. Rinse and repeat.