1. Create systemd unit, put into file /etc/systemd/system/my-service-name.service

[Unit]
Description=Example .NET Web API App running on Ubuntu

[Service]
WorkingDirectory=/var/www/my-service-name
ExecStart=/usr/bin/dotnet /var/www/my-service-name/App.dll
Restart=always
##### Restart service after 10 seconds if the dotnet service crashes:
RestartSec=10
KillSignal=SIGINT
SyslogIdentifier=my-service-name
User=www-data
Environment=ASPNETCORE_ENVIRONMENT=Production
Environment=DOTNET_PRINT_TELEMETRY_MESSAGE=false

[Install]
WantedBy=multi-user.target

2. Enable service "systemctl enable my-service-name"
3. Start service "systemctl start my-service-name"
4. Stop service "systemctl stop my-service-name"
5. View status "systemctl -l status my-service-name"

View logs:

"journalctl -u my-service-name" "journalctl -f -u my-service-name"

Add to Nginx

1. Add file to folder /etc/nginx/sites-enabled/my-service-name

server {
        server_name my-service-name.domain.root;
        location / {
                proxy_pass         http://localhost:XXX;
                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;
        }


    proxy_connect_timeout       600;
    proxy_send_timeout          600;
    proxy_read_timeout          600;
    send_timeout                600;
    
    listen 80;
}

2. Check nginx config "nginx -t"
3. Restart nginx "service nginx restart"
4. Add ssl, run in console "certbot"