should i install mcafee antivirus on my Mac

no, you should not. antivirus apps as well as apps that claim to "speed up" or "clean up" or otherwise "optomize" your Mac are not recommended. all that they do is to interfere with macOS and consume system resources while providing zero protection or benefit. you would do well to avoid them at all costs.

I would also recommend that you read Effective defenses against malware and other threats - Apple Community. it's a long article, but well worth reading every word.