I am reading 'Build RESTful APIs with ASP.NET Web API' article.
I keyed F12, opened Developer Tools window in Internet Explorer but I could not find Start Capturing button. Can you please tell me how to find it, or if it was removed because of the version of Internet Explorer, can you please tell me what button the same is with Start Capturing button?
From the screenshot, it looks like you are using the F12 Developer Tools in Microsoft Edge. If a "Stop" button shows up, you only need to refresh the page to capture network traffic, which works in the same way as the "Start Capturing" button.
For more information of the Network tool, you can consult this doc.