Do I need a security system such as Norton or Macfee for my Mac air laptop?

No, No and No.

AntiVirus, Disk Cleaner, Optimizers, Defrag, VPNs etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS. The Built-in Security of Big Sur is all that is required.

Not needed.

read this... 👉🏼 https://www.apple.com/macos/security/

And to add to gntlmnking's excellent link. Use common sense, don't click on everything you see.

You’re most welcomed.