We had a lot of camera threads here. The first what you can do is to go through the options of the camera app. These options are complicated and have not the best settings by default. Noise reduction is completely off. You get surely a better result but mostly it’s still not satisfying.
Then you could try several apps, even on /e/. Look what I wrote here (forget the Fairphone 4 caption for a moment):
The difference between camera apps is that they have own algorithms for noise reduction, focusing, exposure, sharpening edges, compression, this all has an impact on the picture quality. You have a good chance to find a camera app which takes better pictures than the stock app.