My Iphone 11 won't turn off and I can't open any aps. It started with Facetime showing me no videos but the other party could see me. I am pressing the side button and the volume button to no avail.

I think you are performing the forced restart incorrectly. Try again.

Press and quickly release the Volume Up button. Press and quickly release the Volume Down button. Then press and hold the Side button until you see the Apple logo.

It sounds like you are not timing it properly and when you press and hold the side button, you invoke Siri.

Which iPhone do you have? Does it have a home button? See this for more ways to preform a forced restart.

• iPhone 8 or later: Press and quickly release the Volume Up button. Press and quickly release the Volume Down button. Then press and hold the Side button until you see the Apple logo.
• iPhone 7, iPhone 7 Plus, and iPod touch (7th generation): Press and hold both the Top (or Side) button and the Volume Down buttons until you see the Apple logo.
• iPad with Home button, iPhone 6s or earlier, and iPod touch (6th generation) or earlier: Press and hold both the Home and the Top (or Side) buttons until you see the Apple logo.

This is crap!! I get incoming everything although I can’t respond!! Can’t open apps cand turn it off!!! I’ve done the volume up and down this g about 100 times. My fingers are actually soar!!! What next. Stupid Apple I tried to call and get this. They want my serial number on a phone that won’t open anything. Seriously!!!

I am having the same issue. Have tried this repeatedly and will not work. Siri comes up at bottom of screen.

The serial number should be printed on the box to your phone.

Find the serial number or IMEI on your iPhone, iPad, or iPod touch - Apple Support