Kali Linux Install the VB MacBook

I have downloaded the kali-linux-2018.4-amd64.iso file and have run the graphical installation on the virtualbox on my mac.

After installation, I was able to log in and I saw all the tools available, but when I turned off my terminal and I tried to restart the computer, this screen s & # 39; displays.

I am super new on Linux and consider CEH as an alternative to my daily work.

Please help. Thank you

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