Can not run osx x el capitan in virtualbox

Here is a step by step installation any distribution, if you have correct hardware.

Installing MacOS that is obtained legally on a VM does violate the EULA and terms and conditions of Apple.
It is not illegal to do so as it does not violate any laws.

Given the above - combined with that this topic is unrelated to Zorin OS, Zorin OS operations or installation; It would be a bit hypocritical for the Zorin Forum to take a strong official stance in regards to Zorin OS, but not be respectful of the terms and conditions of other entities.

In order to correct that, I am closing this thread.