Ok, I agree that at the hardware level, you can only make one request at a time. However, the TCP/Networking stack allows for multiple connections to be opened/maintained at the same time (hundreds of connections?) - and when making a HTTP request there is a period of time while the network is inactive waiting for the server to respond so you can use that time to make another request. A lot of web servers can also handle multiple simultaneous incoming connections.
I think in this case the boolean coming into the while loop comes from the output of the bottom GET request which makes them run one after another. You need to remove this dependency (the boolean wire coming in at the bottom). You could also consider having your loops run in parallel, rather than nesting them one inside the other.
Also, according to the help files, you don't need to create/close the client handle unless you need custom headers or login credentials for the request.
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