Wordpress How to make another wordpress installation over the same domain ?

Please fill in any relevant information that applies to you:

• CentOS Version: i.e. / CentOS 7 64bit ?
• Centmin Mod Version Installed: i.e. or 123.09beta01
• Nginx Version Installed: i.e. 1.17.5
• PHP Version Installed: i.e. 7.3.11
• MariaDB MySQL Version Installed: i.e. 10.3.18
• When was last time updated Centmin Mod code base ? : i.e.a week ago
• Persistent Config: Letsencrypt Y

I have touched the functions.php of my wordpress and now i have 500 error wpadmin is not accesible at all. How can i make another wordpress installation over the same domain ? Which steps must I take ? thanks

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