I too have to wait a long time for many web pages to load.
I have good BT Infinity speeds to and from my system, but page loading can take up to 30 seconds for some sites. Also, many web pages appear to have loaded, then, just as you click on something, the page moves down (because someting else has loaded on the page), and you end up on some wrong page. This happens so many many times, and is very frustrating.
I had the same problem with on old W7 PC and a brand new W10 i7 PC with 24 GB RAM, on IE 9, 10, 11, Edge, Chrome and Firefox.
The same problem existed with Home Hub 3 and 5, and conecting directly to the OpenReach modem, and am now using a TP-Link hub. WiFi or Ethernet connection makes no difference.
I have attached to Broadband Availabilty and Speedtest results, and would be very grateful if you can explain what's happening.
What security program are you using and did you use the same one on both W7 & W10?
When you changed from your W7 PC to your new W10 PC did you have the problem right from the start before you loaded any software.
Have you tried running your computer in "safe mode with networking" to see if the web pages still load slowly. This would help rule out any software problems.
Also adding to what gg30340 has said, it may also be an idea to test the latency by performing a traceroute, to google.co.uk for example (using cmd command tracert google.co.uk), and see where the high latency is apperaing.
If on hop 1 the latency is high, which will give you an IP address of 192.168.1.254 if using a HomeHub, then it's more likely to be the computer - on a wired connection it should be around 1ms or below, on a wireless connection can be higher and can vary. Also check that your LAN and WLAN cards are up to date with their drivers, and configured correctly.