Htmlagilitypack C# - select combobox in website and read results

Hello, I'm new to programming and C# and I would like someone to help me create a simple windows forms application with a multiline textbox and a button, in Visual studio with C#.

The objective is to use htmlAgilityPack in order to select a specific value inside a dropdown list of a given website, and get the results that will show up in a div below and paste them into the textbox. (The above will happen without having the website show up in any browser, the information needs to be gathered internally within the application, while the user is doing something else on the computer at the same time)

The website is https://siteapps.deddie.gr/Outages2Public

The attached images explain which is the value to be selected, and which are the results to be pasted inside the textbox.

I will need the source code in order to be able to modify the application further myself.

Please let me know if you have more questions.

Best regards.