Can anyone explain to me why when I click on a link in search the page jumps to another site?

Question

It takes me a different search page altogether or to a page called Marchex.

Answer 1

Your browser is attacked or infected by any hijacker malware

so it can't follow your command and the malware navigates it to the third party sites for advertisement or other commercial issue.

You have to scan your full system by any potential anti-spyware updated in safe mode then in normal mode and fix the infection found. You also need to immunize your browsers all active x contents against all types of spywares,malwares,hijackers,trojans or other online threats.