Enable PHP and CGI in user directory (public_html) in nginx

default.conf

# Default server configuration
#
server {
        listen 80 default_server;
        listen [::]:80 default_server;

        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.php index.html index.htm index.nginx-debian.html;

        server_name example.com;

        # Don't allow access to dotfiles (such as .htaccess)
        location ~ /\. {
                deny all;
        }

        location / {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ =404;
        }

        # Serve user directories php files
        # This MUST appear above both the normal userdir and php location blocks
        # else it will either attempt to load from your main (non-user) site
        # or ask vistors to download PHP files (which can be bad for security)
        location ~ ^/~(.+?)/(.*\.php)$ {
                alias /home/$1/public_html;
                autoindex on;

                # default fastcgi settings
                include fastcgi_params;

                # A bit of added security -- not full proof, but can help
                fastcgi_split_path_info ^(.+\.php)(/.+)$;
                # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini

                # Check that the PHP script exists before passing it
                if (!-f $document_root/$2) {return 404;}

                fastcgi_param   SCRIPT_FILENAME $document_root/$2;
                fastcgi_index index.php;

                fastcgi_pass unix:/var/run/php/php7.2-fpm.sock;
        }
        
        # Enable CGI
        include userdir-fcgiwrap.conf;

        # userdir block
        # Enable files listing in public_html of user home dir
        location ~ ^/~(.+?)(/.*)?$ {
                alias /home/$1/public_html$2;
                index index.php index.html index.htm;
                autoindex on;
           }

        # default php block
        # Enable php in server root
        location ~* \.php$ {
                include snippets/fastcgi-php.conf;

                # default fastcgi settings
                include fastcgi_params;
           
                fastcgi_pass unix:/var/run/php/php7.2-fpm.sock;
        }
}

userdir-fcgiwrap.conf

# Include this file on your nginx.conf to support debian cgi-bin scripts using
# fcgiwrap in user directory: /home/<user>/public_html/cgi-bin/

# Place this file in /etc/nginx/
# And add "include userdir-fcgiwrap.conf;" to site default configuration

# Use this location to enable execution of all script files present in /home/<user>/public_html/cgi-bin/
# location ~ ^/~(.+?)(/cgi-bin/)(.*\..*)$ {

# Enable execution of files with specific extension through cgi
# location ~ ^/~(.+?)(/cgi-bin/)(.*)?\.(py|cgi)$ {

location ~ ^/~(.+?)(/cgi-bin/)(.*)?\.(cgi)$ {
        alias /home/$1/public_html$2$3.$4;

        # Disable gzip (it makes scripts feel slower since they have to complete
        # before getting gzipped)
        gzip off;

        # Check that the PHP script exists before passing it
        if (!-f /home/$1/public_html$2$3.$4) {return 404;}

        # Fastcgi parameters, include the standard ones
        include /etc/nginx/fastcgi_params;

        # Adjust non standard parameters (SCRIPT_FILENAME)
        # fastcgi_param DOCUMENT_ROOT   /home/$1/public_html/cgi-bin;
        fastcgi_param   SCRIPT_FILENAME $document_root;

        # Fastcgi socket
        fastcgi_pass  unix:/var/run/fcgiwrap.socket;
}