I use my phone for my business and am in various business bank account apps as well as scanning confidential business documents with my phone. Am I in any way at risk of a hacker taking over control of my cameras or having access to them and seeing what they see or seeing my screen? On all the official IPhone support pages it seems impossible if not using a jailbroken phone. If it is actually possible, how can I protect my phone?
Apple is continuously patching security problems in all of their OSs with periodic Security updates. In theory if someone exploit one of those security problems in one of your devices before Apple patch it they could gain access to your device and/or data.
That being said, if you are not of specific interest for hackers and you update your devices with all the Security updates when they are released probably you will be fine.
Seeing your screen is not even possible with dedicated apps like TeamViewer. Because iOS simply does not allow such things. And also the app store is the only instance allowed to install something to your phone, so a virus cannot install just because you call it on some suspicious website. Protect your devices? Don’t click on weird links, only use official apps (like do your banking in your app and not clicking on a link to a banking website), change passwords and passcodes regularly.
It is more likely getting your Apple ID/Cloud hacked than your actual phone. Back then when celebs got hacked - they hacked their clouds, not their phones. After that, Apple forced 2FA. And as long as you are not famous, a high ranked manager in a multimillion$ company or whatever, it’s unlikely, you are even of interest for hackers to even find out, what phone you use.
You still panic? Stay offline, buy a Nokia 3310 and remain happy.