I'm in the same existential boat. It's kind of weird, kind of looking forward to things but also feeling like, if I were to just die, I wouldn't really miss anything, because dead people don't have wants or needs.
The way I'm dealing with it is trying to find something meaningful to do with my time here. Something that makes me feel like I'm doing something worthwhile with my life, regardless of outside expectations of what I "should" be doing. I had a bit of an existential crisis a few months back, after getting a pretty decent job in my field. It's not easy to get an opportunity in this field, but as soon as I started the job I felt a sort of dread I had never felt before, thinking about the possibility of spending my life doing this (in the grand scheme of things) utterly meaningless work. So I quit. I went back to an unrelated job I started doing during the pandemic, a self-employed kind of deal. There is no job safety of any kind, but it's a lot more bearable, so I'm making it work. My longer-term goal is to switch careers into something completely different, that I actually feel could make a difference. I'm in that process right now, considering my options, and hoping to go back to school once again this year.
Of course, your circumstances are probably different, but I think the same kind of strategy could be helpful. Trying to find something meaningful, something that you feel like it would be worth your time and effort. Therapy has helped me a lot in that regard. There are some tough choices to be made down the road, but I think that, since I'm already here, I may as well give it a try. I still feel like I'll end up checking out at some point in the future, but for now there are some things that I want to try, to see if I can get some meaning out of them. Offing myself is always an option, but for now I want to try other things.
So, after all this rambling, I guess my advice would be "try to find something that's meaningful to you, and go for it". I am a fan of therapy because it has helped me quite a bit, so I suggest giving it a try if you haven't and is within your means. But, in general, you need to think long and hard about what really matters to you, and then do what you can to focus your energy on that.