avoid .html extension cPanel code example
Example: htaccess remove .html
#remove html file extension-e.g. https://example.com/file.html will become https://example.com/file
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.html -f
RewriteRule ^(.*)$ $1.html [NC,L]