Following are images of SCAM web pages that ‘jam’ your Browser: Chrome, Safari, Edge,  etc and MAC, PC LINUX, Android, iPad etc are all equally susceptible! Page LOOKS like you have a virus or something bad when you do not: 

Your Anti Virus will not say anything. because a Web Page is NOT a Virus.

It proves  hard to close or exit the screen as the web page maker suruptiotiosly hides all the ‘close’  ‘minimize’  ‘exit’ buttons, etc..

NEVER call the number. NEVER answer unknown calls. NEVER click Any links at such pages NEVER respond in ANY way,
because that itself is the Scam.

Try the [Esc] Key. This MAY bring up Navigation buttons again so you can Exit. 

MAC: Use [Command-Option-Esc] and KILL safari or Chrome of Firefox
PC: Use:: [Ctrl-Alt-Delete] to kill Chrome, Edge, Firefox, Etc.

These Pages show up in several ways:
a) the Pagemaker has lured Google into showing this result when searching for something innocuous. Often: the result itself is harmless but directs you to harmful page. Worse, NOT EVERY redirect happens and often it re directs 5-10 times AT RANDOM so it’s hard to report the result to Google, etc…
b) the page server you usually visit has been ‘invaded’ and itself compromised to show the page- your usual Weather or News page may suddenly show this!