Your Mac has multiple layers of security built in including the equivalent of antivirus. I argue that installing antivirus on the Mac actually decreases it's security by introducing vulnerabilities and the potential for unintended information disclosure to an OS that was not at threat in the first place. In addition, antivirus on the Mac is the number one cause of instability, performance problems, and OS upgrade problems. Think very carefully before ruining your brand new Mac with ANY unnecessary software including antivirus, boosters, optimizers, cleaners, monitors, enhancers, or any software that has a name including these terms.
The ONLY way that your Mac will ever be threatened by Malware is if YOU PURPOSELY INSTALL IT. Every threat to the Mac involves the same series of events. If you manage to infect a Mac, it's because YOU are responsible for several of the the following mistakes:
1) Not keeping your Mac OS updated
2) Disabling some of the built-in Mac OS security layers like Gatekeeper and SIP
3) Not keeping your Browser updated
4) Installing obsolete plugins that are unnecessary and security threats (e.g. Java, Flash, Shockwave, Silverlight, etc).
5) Either purposely (e.g. pirated software) or being fooled into initiating the download of untrusted software containing a trojan installer
6) Ignoring the warning that most browsers give about untrusted software downloads at completion
7) Overriding Gatekeeper when warned that the software can't be run because it's not trusted or from the App Store.
8) Purposely entering your administrative credentials to complete the installation
That's right, you would need to do all of that to infect your Mac with Malware.
If you don't believe me, go ahead and Google "Bitdefender Mac". What you will find is not posts of people where Bitdefender (or any other antivirus) helped a Mac user out. Instead, you will find a massive number of posts of users that are having unexpected crashes or major performance problems with their Macs and want to know how to uninstall these unnecessary software applications.
If you insist on installing antivirus on your Mac then choose Malwarebytes. And, when installing it make sure that you only use it as an on-demand scanner.