You can just use nextjs as you would normally do. If you only want a full frontend application, use react. It's only clientside

https://nextjs.org/docs/app/building-your-application/deploying/static-exports to export it to static files, but you still need a server/filehost to serve the files

and if you export them like that, you have some disadvantages, that are also mentioned on the page

ahh i dont really understand
do i need to use react-router to handle dynamic routes?

nah, you need to generate every single route using generateStaticParams(). Then every page can be generated during build time and you can still have dynamic pages