Make sure the url has the preceding http:// or https://. Without it selenium will not see it as a valid url and will not navigate to the page. I don’t recall if either selenium or SeleniumLibrary throws an error but trace loglevel might show something.
You are not asking for a correct URL, like EdManlove asked.
You show us the result of screenshot, but in the previous image we can see that the argument was not starting with http:// or https:// (at leas it seems).
But you should really confirm if the URL is working in a clean browser session. Start a browser in Incognito mode and enter that URL.
As I read this I see the opening with a blank page but then using the Go To keyword to navigate to a page which is a perfectly fine way to operate. As to why the blank screen I was thinking this could occur with a javascript error causing the page not to fully load or render. I see you got a 200 response. I would throw in a Get Source keyword after the go to and see what is in there. That might reveal more about what is going on …
Using the string format for the Selenium options,the following should set that additional argument for a proxy server, replacing 0.0.0.0:0000 with your server either the IP or url,
Open Browser None Chrome options=add_argument("--proxy-server=0.0.0.0:0000")