Check out example codes for "open url in c#". It will help you in understanding the concepts better.
Code Example 1
System.Diagnostics.Process.Start("http://google.com");
Code Example 2
var uri = "https://www.google.com";
var psi = new System.Diagnostics.ProcessStartInfo();
psi.UseShellExecute = true;
psi.FileName = uri;
System.Diagnostics.Process.Start(psi);
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