do ipad experts recommend antivrus

No.

There are no true Antivirus Products available for iOS/iPadOS. Those that claim to provide AV protection are little more than “snake oil”, have negligible (if any benefit) and for Apple devices should generally be avoided. Very often, Apps of this nature introduce more issues than added benefit.

Unlike traditional Operating Systems with which you may be familiar, iOS/iPadOS uses a sandboxed security architecture. As such, Apps cannot access any data outside of their own sandbox - and cannot access the storage and resources of other Apps. As such, it is impossible for an Anti-Virus App to scan the filesystem.

While McAfee, Norton and similar Apps have very little if any benefit, there are useful security enhancements and mitigations that can add security to your device - such as adding a good content/ad-blocking product (e.g., 1Blocker) - and use a security-focused DNS provider (e.g., Quad9) and encrypted DNS transport protocols (DoH, oDoH, DoT).

No.

iPads are heavily sandboxed just like iPhones. You have to do some terrible things to it to make it vulnerable. We've used iPads for over 12 years and never had need to install such fearware.

You may see popups saying they detected a virus. 100% scams. Remember: no one—not even the minor deities on Mount Apple—can "see" what is or is not on your device unless you expressly give them permission for remote access. They are scam pop-ups some websites like to show to make more money.

Also don't fall for "client-side" VPNs that spend $millions$ a year on TV adverts. Most end users never need them. If you use your iPad for company business and they think you need one, they will issue you one that is fully compatible with their IT systems. Some cheapo VPNs actually pose security risks.