Choosing a problem to solve, rather than starting with what you want to build, is the best way to start a business.
Some search for that problem, landing on a problem that they don't have, but others do, or they think that they do. This often leads to synthetic solutions that either don't solve the problem, or the problem isn't important enough, causing demand for the solution to disappear as soon as it's built.
If you have a problem and focus on solving that, you will have created a solution that works optimally for at least one person. There are others like you, so finding them and presenting your solution will be well-received. Congratulations, you're further on than most.
That's rewarding in itself. Something I've learnt, though, is that before solving the very real problem with an elegant solution, there needs to be a checkpoint. Will creating and maintaining this solution give me sustainable joy?
If not, when your solution is out there, it will be a burden rather than a joy.
For your solution to bring you sustainable joy, it might need to pay for a couple of coffees a month, give you the admiration of your peers, generate enough revenue so that you can quit your day job, or simply be something you look at with pride.
I've put good solutions out into the world, and invested in some, that have turned out to be more a burden than a joy. It's amazing that they're solving real problems elegantly: I have delivered more poor solutions and solutions to flimsy problems than I dare to count, so believe me, I really appreciate the feeling when someone gets great value from the thing you've built.
What happens though when the elegant solution is more a burden than a joy is that it degrades. As it doesn't give us what we need from it, it suffers from neglect, eventually no longer solving the problem as capably as it should.
Now, when I find a good problem and solution pair, I'm mindful about what I expect back from it. If the solution can't give me that, I don't proceed. In this way, I curate the problems I'm working on and the solutions I'm putting out into the world and backing.