How to Encrypt and Decrypt Files With GPG on Linux

https://www.howtogeek.com/427982/how-to-encrypt-and-decrypt-files-with-gpg-on-linux/

boot virtualbox from usb

https://www.aioboot.com/en/boot-from-usb-in-virtualbox/

2 Ways to Create an ISO from a Bootable USB in Linux

https://www.tecmint.com/create-an-iso-from-a-bootable-usb-in-linux/