Install, PHP, DB, Nginx first.

$ adduser nginx
$ adduser nginx sudo
$ su - nginx
$ exit

$ cd /var/www/html
$ sudo wget https://getgrav.org/download/core/grav-admin/1.7.48
$ sudo unzip 1.7.48
$ sudo mv grav-admin grav
$ sudo chown -R www-data:www-data /var/www/html/grav

Nginx Config File

$ sudo nano /etc/nginx/conf.d/grav.conf

server {
listen 80;
server_name grav.example.com;
root /var/www/html/grav;
index index.html index.php;
location / {
   try_files $uri $uri/ /index.php?$query_string;
 }
   location ~* /(\.git|cache|bin|logs|backup|tests)/.*$ { return 403; }
   location ~* /(system|vendor)/.*\.(txt|xml|md|html|yaml|yml|php|pl|py|cgi|twig|sh|bat)$ { return 403; }
   location ~* /user/.*\.(txt|md|yaml|yml|php|pl|py|cgi|twig|sh|bat)$ { return 403; }
   location ~ /(LICENSE\.txt|composer\.lock|composer\.json|nginx\.conf|web\.config|htaccess\.txt|\.htaccess) { return 403; }

location ~ \.php$ {
   fastcgi_pass unix:/var/run/php/php8.2-fpm.sock;
   fastcgi_split_path_info ^(.+\.php)(/.+)$;
   fastcgi_index index.php;
   include fastcgi_params;
   fastcgi_param SCRIPT_FILENAME $document_root/$fastcgi_script_name;
 }
}

$ sudo nginx -t
$ sudo systemctl restart nginx
$ sudo systemctl status nginx

If you find issues with the scheduler in Grav, run the following command:
$ sudo crontab -u www-data -e
And add this line to the bottom of the file:
cd /var/www/html/grav;/usr/bin/php bin/grav scheduler 1>> /dev/null 2>&1