If you're having trouble, I can help you fix it if you tell me: What is your (Windows 11, Mac M3, etc.)? What is your Guest OS (Ubuntu, Windows 10, Kali)? What error message are you seeing?
In a headless Linux VM, you can install Guest Additions like this: guest additions iso virtualbox
/Applications/VirtualBox.app/Contents/MacOS/VBoxGuestAdditions.iso Linux: /usr/share/virtualbox/VBoxGuestAdditions.iso Installation Guide: Step-by-Step 1. Mount the ISO If you're having trouble, I can help you