How to host files in subfolder

@emrah In the web container, since I see these

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

in nginx.conf, added some lines to /etc/nginx/sites-enabled

root /var/www/html;

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

        server_name _;

        location /monitoring/ {
                proxy_pass http://<public-ip>:<port>;
        }

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

Adter firing - service nginx reload, logs from /var/log/nginx/error.log

2021/05/25 20:52:39 [emerg] 1358#1358: unexpected "}" in /etc/nginx/sites-enabled/default:55
2021/05/25 20:53:00 [info] 1390#1390: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/25 20:53:02 [info] 1431#1431: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/25 20:53:04 [info] 1472#1472: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/25 20:53:08 [info] 1513#1513: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/25 20:53:10 [info] 1548#1548: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/25 20:53:35 [info] 1591#1591: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/25 20:53:39 [info] 1632#1632: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/27 16:39:05 [info] 2207#2207: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/27 16:42:36 [info] 2251#2251: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/27 16:46:16 [info] 2297#2297: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/27 16:47:37 [info] 2330#2330: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63
2021/05/27 16:47:42 [info] 2363#2363: Using 32768KiB of shared memory for nchan in /etc/nginx/nginx.conf:63

After firing - /etc/init.d/nginx reload , logs

2021/05/27 16:47:42 [error] 2339#2339: MEMSTORE:01: my procslot not found! I don't know what to do!
nginx: worker process is shutting down: /build/nginx-Cjs4TR/nginx-1.14.2/debian/modules/nchan/src/store/memory/memstore.c:1616: nchan_store_exit_worker: Assertion `0' failed.
2021/05/27 16:47:42 [alert] 1635#1635: worker process 2339 exited on signal 6
2021/05/27 16:47:42 [alert] 1635#1635: shared memory zone "memstore" was locked by 2339
2021/05/27 16:47:42 [error] 2341#2341: MEMSTORE:03: my procslot not found! I don't know what to do!
nginx: worker process is shutting down: /build/nginx-Cjs4TR/nginx-1.14.2/debian/modules/nchan/src/store/memory/memstore.c:1616: nchan_store_exit_worker: Assertion `0' failed.
2021/05/27 16:47:42 [alert] 1635#1635: worker process 2341 exited on signal 6
2021/05/27 16:47:42 [alert] 1635#1635: shared memory zone "memstore" was locked by 2341
2021/05/27 16:47:42 [error] 2340#2340: MEMSTORE:02: my procslot not found! I don't know what to do!
nginx: worker process is shutting down: /build/nginx-Cjs4TR/nginx-1.14.2/debian/modules/nchan/src/store/memory/memstore.c:1616: nchan_store_exit_worker: Assertion `0' failed.
2021/05/27 16:47:42 [alert] 1635#1635: worker process 2340 exited on signal 6
2021/05/27 16:47:42 [alert] 1635#1635: shared memory zone "memstore" was locked by 2340
2021/05/27 16:47:47 [alert] 2303#2303: *385 open socket #23 left in connection 14
2021/05/27 16:47:47 [alert] 2303#2303: *386 open socket #25 left in connection 15
2021/05/27 16:47:47 [alert] 2303#2303: aborting

You have a syntax error in your conf file on line 55:

 unexpected "}" in /etc/nginx/sites-enabled/default:55

Maybe a missing semicolon?