The problem with forums like these is that you're offering advice to people you don't know and have no measure of their understanding, that doesn't mean we have to quit when the going gets tough.
To clear up the points you've made Microsoft Edge is a browser (an internet browser) and a URL is the website address that you type in (www.bt.com)
Copy and paste the following into the address bar in Microsoft Edge and then press Enter
edge://settings/siteData
You will see two 'Buttons' at the top of the screen, click on the one marked Remove All. Note that while this could clear your problem, it will also log you out of any websites that you may be logged in to (e.g. Facebook)
