Apache .htaccess to NGINX RewriteRules Port

So, I am actually trying to port the RewriteRules from Apache to NGINX but it seems I am not able to completely port out.

Actually, on my server I do have a running site on https://example.com domain and /var/www/html/ path on the server. What I am trying to do is install a custom script in a subdirectory under the var/www/html/subdirectory path and domain https://example.com/subdirectory.

The problem is rewrite rules are not working and even 404 not found errors are occuring. Kindly help me.

My Apache .htaccess file:

RewriteRule ^page/?$ pages/page.php [L]
RewriteRule ^about/?$ pages/about.php [L]
RewriteRule ^privacy-policy/?$ pages/privacy-policy.php [L]
RewriteRule ^contact/?$ pages/contact.php [L]
RewriteRule ^terms/?$ pages/tos.php [L]

RewriteCond %{REQUEST_FILENAME} -f
RewriteRule ^(.+) - [PT,L]

RewriteRule ^sitemap-([0-9]+).xml$ parts/sitemaps/sitemap-$1.xml [QSA,L]

RewriteRule ^(.*)/(.*)/(.*)/(.*)/?$ index.php?bank=$1&state=$2&district=$3&branch=$4 [QSA,L]
RewriteRule ^(.*)/(.*)/(.*)/?$ index.php?bank=$1&state=$2&district=$3 [QSA,L]
RewriteRule ^(.*)/(.*)/?$ index.php?bank=$1&state=$2 [QSA,L]
RewriteRule ^(.*)/?$ index.php?bank=$1 [QSA,L]

and NGINX config file that I have tried to port:

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;

  server_name localhost;

  location /
  {
    try_files $uri $uri/ =404;
  }

  # pass PHP scripts to FastCGI server
  location ~ \.php$
  {
    include snippets/fastcgi-php.conf;
    #       # With php-fpm (or other unix sockets):
    fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
    #       # With php-cgi (or other tcp sockets):
    #       fastcgi_pass 127.0.0.1:9000;
  }

  location /subdirectory
  {

    root /var/www/html/subdirectory;
    index index.php;
    try_files $uri $uri/ /index.php$args$query_string

    location ~ ^/(.+)
    {
    }

    location /page
    {
      rewrite ^/page/?$ /pages/page.php break;
    }

    location /about
    {
      rewrite ^/about/?$ /pages/about.php break;
    }

    location /privacy
    {
      rewrite ^/privacy-policy/?$ /pages/privacy-policy.php break;
    }

    location /contact
    {
      rewrite ^/contact/?$ /pages/contact.php break;
    }

    location /terms
    {
      rewrite ^/terms/?$ /pages/tos.php break;
    }

    location /
    {
      if (-e $request_filename)
      {
        rewrite ^/sitemap-([0-9]+).xml$ /parts/sitemaps/sitemap-$1.xml break;
      }
      rewrite ^/(.*)/(.*)/(.*)/(.*)/?$ /index.php?bank=$1&state=$2&district=$3&branch=$4 break;
      rewrite ^/(.*)/(.*)/(.*)/?$ /index.php?bank=$1&state=$2&district=$3 break;
      rewrite ^/(.*)/(.*)/?$ /index.php?bank=$1&state=$2 break;
      rewrite ^/(.*)/?$ /index.php?bank=$1 break;
    }

    location ~ /subdirectory /(.+\.php)$
    {
      include snippets/fastcgi-php.conf;
      # With php-fpm (or other unix sockets):
      fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
      # With php-cgi (or other tcp sockets):
      # fastcgi_pass 127.0.0.1:9000;
    }

  }
}