SKevo HOANGVANHIEP were you able to apply the correct URL rewrites? Your forum's assets (forum.css, forum.js, etc...) seem to not be accessible, so I think that there's something wrong with the static file server for your assets folder
HOANGVANHIEP SKevo I don't quite understand it can you help me https://tuoitrelaptrinh.eu.org/public/
luceos HOANGVANHIEP that's because the css and js aren't served by Flarum, they are generated (as shown HOANGVANHIEP). But because they are throwing a 404, those files aren't provided by your webserver, so something is wrong there.
SKevo HOANGVANHIEP if I open https://tuoitrelaptrinh.eu.org/public/assets/, it shows a 403 status code. Have you correctly set up Flarum permissions as described here? TL;DR try running via SSH, if you have access to that chmod 775 /home/haoxvntk/public_html -R; chown www-data:www-data /home/haoxvntk/public_html -R
