Unwanted Ads

I am running Windows 10 on my Lenovo laptop.  I use both the new version of Microsoft Edge and Chrome for my browsers.  When I started getting a new pop-up advertising intrusion that opens an entirely new tab unrelated to the page I'm going to - as well as an ad that slides in from the right side of the screen - it was suggested that I install AdBlocker, which I did.  The problem seemed to resolve, but now it's back ... and there's a new problem that seems related.  Almost every time  I go to a new page, the page I'm going to opens fine, but an unrelated page also opens up.  Sometimes it's just an unrelated page (which I just need to close), and sometimes it's a page that's blocked by my Norton Internet Security (see message below).  Is there a stronger ad blocking software, or something I can do to track down why this is happening and clean up my browsers?

Thanks,

Phil