While using an antivirus program is essential on a Windows PC, it is possible to do without one on a Mac. Apple products are indeed known to be much less targeted by hackers. Nevertheless, it is advisable to adopt the right measures to avoid unnecessary exposure to malicious software.
First of all, remember to update your operating system and your various programs as soon as necessary, and to regularly back up the contents of your Mac on an external hard drive via Time Machine. On a daily basis, it is recommended to install only software from reliable sources. To do this, go to the "Privacy and Security" section in the "System Settings" of your Mac and specify these sources: App Store only or App Store and identified developers.
There are also free solutions that can check your Mac for viruses. These programs, such as Bitdefender Virus Scanner, allow you to scan the contents of your hard drive whenever you want. They immediately detect the presence of malware or an infected file, which is then placed in quarantine before it can be deleted. This solution certainly has its limits, but it allows you to quickly ensure that your computer is not corrupted, by, for example, running it at the end of a session before turning off your Mac.
Finally, you can always pay to install a comprehensive software suite to monitor the proper functioning of your Mac in real time. However, these kinds of solutions, offered by Intego, McAfee or even Kaspersky, tend to reduce your computer's performance a little. But with this level of protection, you should be safe from the slightest threat.