Waiting for a website means it's waiting to get a reaction. If that doesn't come as soon as you want, in essence there's nothing you can do about it.
First, if you have such trouble with a website, try to do exactly the same (at the same moment) with another device (say, your cell-phone or your friends laptop) via the same Internet-connection (Ethernet or WiFi, router, modem, ISP). Only If that's as fast as normally and your Mac is slow, it's likely to be a Mac issue. If that's slow also, it's an issue of your router, modem, connection to the ISP and beyond (including the website itself).
Then, if you use WiFi and this happens, it's possible that the connection is slow because the router or the connection is overloaded with other requests (maybe even from your neighbour, if he cracked yours or you're using his). Then the solution is to turn of WiFi and connect wired (Ethernet cable). If that's normal, you know where to look.
Kees
This problem is EXTREMELY frustrating. Sometimes (occurs randomly), I am unable to open webpages because all my browsers (Chrome, Safari, Firefox) stall on a "Waitng for website..." dialogue. I can go on basic websites like Google and Yahoo, however I cannot go on ANY other page or link without this error coming up. My preferred browser is Chrome. This has happened on and off for the past couple months and it's frustrating the hell out of me. Any help to resolve this connection issue on my 2015 MacBook Pro would be of great help!

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