Preload for script and css with file build in Nextjs

Question

I have question and still not found the solution for apply preload css and js when run

yarn build ; yarn start

I have found this in website https://vercel.com/ and want apply that in my website use nextJs version 12.3.1

Currently my script and css after build have link with rel prefetch and performance in gtmetrix is not good.

gtmetrix score i got

Thanks for read and feel free to comment solution.