VirtualBox - ArchWiki - Arch Linux
https://wiki.archlinux.org/title/VirtualBoxRead from VirtualBox/Install Arch Linux as a guest#Install the Guest Additions if your guest is Arch Linux, otherwise read the official VirtualBox help. No 64-bit OS client options. When launching a VM client, and no 64-bit options are available, make sure your CPU virtualization capabilities (usually named VT-x) are enabled in the BIOS.