Serve static website and php application with nginx

I have a static website (MY_WEBSITE) and a php app (MY_PHP_APP) that I want to install in a server using nginx. I am still in the testing phase in localhost.

I am not too knowledgeable with nginx and I think I am doing something wrong.

I stored the website under /var/www/MY_WEBSITE (it contains an index.html file) and the php app under */var/www/MY_PHP_APP (it contains an index.php file). Read privileges and www-data user are correctly set up, and php8.1-fpm socket is installed.

This is my nginx configuration:

server {
    listen 80 default_server;
    listen [::]:80 default_server;

    index index.php index.html index.htm index.nginx-debian.html;
    server_name localhost;

    location / {
        root /var/www/MY_WEBSITE;       
        try_files $uri /index.html =404;
    }

    location /MY_PHP_APP {
        root /var/www/MY_PHP_APP;
        try_files $uri $uri/ /index.php$is_args$args;
    }
    
    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/run/php/php8.1-fpm.sock;
    }

    location ~ /\.ht {
        deny all;
    }
}

I can access my website under localhost, but I get 404 when I visit localhost/MY_PHP_APP. What I am doing wrong?

source https://stackoverflow.com/questions/77246388/serve-static-website-and-php-application-with-nginx