Why 502 error on ubuntu + nginx + asp.net?

Question

Nginx

Good afternoon. I'm not an administrator, but I'm trying to figure out how to host a site on asp.net under bare ubuntu 20.04. Here is what I did:

1. Installed nginx
   
2. From the official microsoft documentation, I installed sdk, dotnet runtime and aspnetcore (the site itself starts up without errors, I think it's in nginx)
   
3. I tried to install php-fpm and accordingly change the settings in the config for it
   

The site is located at /var/www/html/publish

/etc/hosts

127.0.0.1       localhost
127.0.0.1       myDomen.ru
194.87.232.12   ubuntu20.ruvds.com      ubuntu20

# The following lines are desirable for IPv6 capable hosts
::1     localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

/etc/nginx/sites-enabled/default

# Default server configuration
#
server {
        listen 127.0.0.1;
        #listen [::]:80 default_server;

        # SSL configuration
        #
        # listen 443 ssl default_server;
        # listen [::]:443 ssl default_server;
        #
        # Note: You should disable gzip for SSL traffic.
        # See: https://bugs.debian.org/773332
        #
        # Read up on ssl_ciphers to ensure a secure configuration.
        # See: https://bugs.debian.org/765782
        #
        # Self signed certs generated by the ssl-cert package
        # Don't use them in a production server!
        #
        # include snippets/snakeoil.conf;

        root /var/www/html/publish;

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

        server_name myDomen.ru www.myDomen.ru;

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

                proxy_pass      http://127.0.0.1:5000;
                proxy_http_version 1.1;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection keep-alive;
                proxy_set_header Host $host;
                proxy_cache_bypass $http_upgrade;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header X-Forwarded-Proto $scheme;
        }

/etc/nginx/nginx.conf

user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
        worker_connections 768;
        # multi_accept on;
}

http {

        ##
        # Basic Settings
        ##

        sendfile on;
        tcp_nopush on;
        tcp_nodelay on;
        keepalive_timeout 65;
        types_hash_max_size 2048;
        # server_tokens off;

        # server_names_hash_bucket_size 64;
        # server_name_in_redirect off;

        include /etc/nginx/mime.types;
        default_type application/octet-stream;

        ##
        # SSL Settings
        ##

        ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3; # Dropping SSLv3, ref: POODLE
        ssl_prefer_server_ciphers on;

        ##
        # Logging Settings
        ##

        access_log /var/log/nginx/access.log;
        error_log /var/log/nginx/error.log;

        ##
        # Gzip Settings
        ##

        gzip on;

        # gzip_vary on;
        # gzip_proxied any;
        # gzip_comp_level 6;
        # gzip_buffers 16 8k;
        # gzip_http_version 1.1;
        # gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

        ##
        # Virtual Host Configs
        ##

        include /etc/nginx/conf.d/*.conf;
        include /etc/nginx/sites-enabled/*;
}

I run it without a service using sudo dotnet myProject.dll, everything runs without errors

Error when accessing the site from /var/log/nginx/error.log

2021/12/28 01:24:11 [error] 5497#5497: *4 connect() failed (111: Connection refused) while connecting to upstream, client: 196.196.41.68, server: myDomen.ru, request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:5000/", host: "1434.134.123.123:80"

I've tried everything, I think I don't know something that is rarely talked about.
I will be glad for any help! Thank you