I would imagine the simplest setup for this would be something like a Raspberry Pi or Arduino with some thermometers working off the headers. A quick Google turned up this guide:

https://medium.com/initial-state/how-to-build-a-raspberry-pi-temperature-monitor-8c2f70acaea9

Which is using something called Initial State (though its not free) as the web dashboard where the data is streamed to, but it wouldn't be too difficult to modify this to work with something home baked that runs off your own server. Might be a good starting point!

You do not really need to do all the work and have arduino.
If there are any wifi assisted devices using a number of the specs you just need to have https://www.home-assistant.io/ Home assistant setup on a machine, docker, VM etc. Runs in a lot of environments.
You have your devices, detected and then they will most likely do stuff and have options out the box and feed into a heap of extensions/plugins available etc for that.
If you need to do more home assistant has full API so you can feed it to a web page.
BUT home assistant interface is web based and you can set it to access your home assistant across the internet so it can be very likely on the dashboard you setup etc you wont need to do anything more. You can do sending emails or text messages etc all through it if needed, send to devices so google can announce something is overheating and so on.

https://forum.arduino.cc/t/error-with-esp8266-libray/578978

Looks like you might not need to install that library separately? 

This guy has your error and fixed it installing some missing dependencies:
https://github.com/Aircoookie/WLED/issues/584

Not across their coding setup but when you get those sorts of library issues/errors it means multiple versions of the same library being called.


If there is a build/library/package manager just go in and remove the ESPAsyncTCP-master one.
Often if you switch your build or branch for a package etc the old legacy is there so if you run a code Build it runs both. There would be a clean/clear function to clear out?
That or just go to that folder and delete the master one or other depending on which one your actually including in your project.

Looks like it's the other one causing the issue, so just copy this folder out of this location (in case you need to put it back): C:\Program Files (x86)\Arduino\libraries\ESPAsyncTCP

That means the library the code needs is not there so it does not understand what that does.
So Either...
You removed the wrong one
Part of your code is using one and another part is using the other and there are conflicts.

Which board are you using, you said you ordered an arduino but the guide is for an ESP?

I assume you’re using a Node MCU if you can tell me which one and pastebin your code I’ll have a go this evening and if I can get it working I’ll send you the ide

You have two issues:

The code you copied is wrong, this line shouldn't have an S on the end:
 #include <ESPAsyncWebServer.h>S

In your logs it was showing the location with -master on the end you should have removed this from the folder title.

If you still can't get it to work let me know