do I need a security software for macbookpro

Not unless your school or business requires it.

If for some reason you believe you are infected with malware, then you can run MalwareBytes to clean the system, but it is not necessary to run it all the time. Just be careful about the websites you visit, the files you download and run, and the links you click on in e-mails and on websites. Whenever macOS prompts you for your password to approve an app, just make sure you take a moment to think about what you are doing and whether the app is legitimate and from a legitimate source.

Not in my opinion. And many of them that are marketed as such cause more issues than they prevent.

Also see: macOS - Security - Apple

Read Effective defenses against malware and other threats - Apple Community.

So far none of them offer any addition protection over Apple software that kept up to date.