Answering what I would do won’t help you because we don’t share the same context. (I’m doing what I think is the most important thing in the world but I doubt you’d make that decision for yourself)
When considering work it is important to differentiate happiness and satisfaction. Happiness is fleeting and empty calories. Satisfaction can persist even through pain, discomfort and sadness.
Climbing a mountain might be hard (feet hurt, out of breath, tired) but the satisfaction is worth it. Working as an ER doctor might be hard but every day you are providing necessary assistance to the people with the most urgent need. That might be the most important thing in the world to you.
That’s the question to answer for yourself:
What is the most important thing in the world?
What is the best way to make the most important thing in the world better?
Therein lies satisfaction. However, you may also with to consider other factors: what can you get paid to do. What can you get good at, what do you like doing. (There’s some Japanese word for the overlap between those things — which I can’t remember because I’ve never been good at languages. See above)