It seems that your web-browser or computer is hijacked by browser hijacker or other malware. I would suggest you to check installed browser extensions. In addition, reset your web-browser settings and use malware removal tools listed here – Free Malware Removal Tools.
If you’re seeing unwanted pop-ups or ads in your web-browser, you might have an adware installed on your computer. Use the following guide to stop pop-up ads and remove malicious software. Or ask for help here.