My bad, I've pasted the wrong URL
https://www.amazon.com/gp/sendtokindle
Here is a screenshot how it looks on Windows.
You can
disable that "Archive document in your Kindle Library" option if you don't want the book you're sending to be saved onto your free cloud storage (if it is saved then it is displayed in "All" section on Kindle home screen), and you also need to choose with device or app you would like to send the document to.