Should I give "Full Disk Access" to Bit Defender on my iMac?

That is a trick question.

If you want to use BitDefender, then yes, you must give it Full Disk Access in order for BitDefender to be able to access the entire drive.

However, as the other contributors have mentioned, you should not be using any anti-virus apps (or cleaning/optimizer apps, or third party security software) since they usually cause more problems than they solve because the interfere with the normal operation of the OS. In the latter case, the answer is no and you should uninstall BitDefender by following the developer's instructions.

If you want to protect the computer & yourself, then read the following article written by a respected forum contributor (in addition to the links already provided by others here):

Effective defenses against malware and other threats - Apple Community

The only acceptable answer will be to remove BitDefender. You should not install AntiVirus on a Mac. Don't just take my word, view the issues other users have experience specifically with BitDefender:

BitDefender - Causes my iMac to crash - Apple Community

Is Bitdefender needed or of any use? - Apple Community

Bitdefender - Apple Community

Is bitdefender a good antivirus for MacBo… - Apple Community

workingitout wrote:

Hi I have a iMac & have Bitdefender Anti Virus on it. A window has appeared when I went into Bitdefender Antivirus that says GIVE ACCESS TO YOUR ENTIRE DISC! What should I do please someone, it looks like it will not let me scan my iMac unless I give BIT DEFENDER ANTI VIRUS ACCESS. Could someone who is good with iMacs & Anti Virus Software please advise me what to do please? If I do not give the Anti Virus Access, I cannot scan my iMac. Why do they force you into situations like this?

I would appreciate if someone could please tell me what to do? Thank you.

[Re-Titled by Moderator]

Third party AntiVirus is not recommended— it typically does nothing but add issues to the macOS and competes directly with Apple’s own built in security:

macOS - Security - Apple macOS - Security - Apple

Apple Platform Security - Apple Apple Platform Security - Apple Support

leroydouglas has already provided you with excellent advice.

The number one thing you need to do for Macs, related to security, is to keep them updated. Just about every new macOS update includes updates to the operating system defenses against malware.

In addition, if you are running macOS Monterey or later, the Mac's operating system is in a "read-only" volume on it internal drive.

FWIW, I have been using Macs since the Apple IIc. I have yet to encounter any of my Macs getting a virus. IMHO, having an 3rd-party AV app is just a waste of money.