How can I be more grateful?

I'm very lucky and very privileged. I haven't known a lot of struggle, my parents are alright, i have a roof over my head, i have a car, and a job. I'm not ill. I have a good life at 21, where there isn't a lot that I have to worry about.

But I'm constantly uncomfortable. Something, I literally don't know what, eats at me whenever I have a moment to think. It's this crazy, unbearable need to just do something, very specific, but I just don't know what. I don't. I've been trying really hard to think of what would finally fucking satisfy me, when I have everything a person could need. But i still feel so hollow and hopeless. For fucking what?

I feel like such an ungrateful piece of shit. I have no reason to feel the way I do while so many other people around me genuinely do. I don't have anything i could possibly fucking complain about, but here I am. Down on myself. For. Fucking. What?

What can I do? I know I'm a lucky person, I've had a pretty good life, how can I appreciate the things around me? How can I be better in supporting the people in my life that do struggle?

How can I get rid of this constant discomfort? Is it a cycle I've gotten stuck in within my own head that I just need to break?

If you've experienced this, I would love to know what you have to say. Thank you.