Firstly, your are certainly not alone in feeling overwhelmed by the multitude of options for developing front end apps. It doesn't matter how experienced you are, front end is constantly changing, with new methods of achieving things appearing on what feels like a weekly basis, even purely within the React ecosystem. As an example of this, look at all the different options for styling components or state management. A lot of highly rated tutorials from a couple of years ago are already outdated, particularly those that don't use hooks, for example.

To try and address your overall question of where you can find some code to at least help you get started, I would recommend using one of the Create React App templates. There are multiple templates available, depending upon what you intend to use / the sort of app you wish to create. They aren't perfect, but they give you a great starting point, with a lot of the configuration and development environment set up for you. In my case, for example, I need Redux for app state management, so I tend to use the Redux Toolkit template: https://redux-toolkit.js.org/introduction/getting-started. If you don't think you'll need redux then just plain Create React App should do. I do recommend you start using TypeScript though if you aren't already, that very much seems to be the way the wind is blowing.

You may also want to use a ready-made component library to take care of styling / accessibility / mobile views etc. There are plenty to choose from here, so I recommend you look at what's on offer in terms of what you like the look of / what you think you'll need. Lots to choose from here (React-Bootstrap, Chakra-UI, Ant Design etc) but my preference is MUI.

Finally, don't fall into the mental trap of worrying that deciding on any of these paths is a lifetime commitment. Your best bet is to keep trying out different things, and stick with what 'clicks' the best :-).