Run full hassos on raspberry pi is?

Can someone link to a way to install full hassos on a raspberry pi 4 running raspberry pi os from a usb flash drive and inside that run hassos in a virtual machine? I tried and can’t get it to just boot from a flash drive and wanted a full desktop anyway.

This link helped me “How to Boot Raspberry Pi 4 From a USB SSD or Flash Drive | Tom’s Hardware” https://www.tomshardware.com/amp/how-to/boot-raspberry-pi-4-usb

After you update the pi eprom to boot from USB, you flash the hassio image onto the device you want to boot from.

How do I run hassos as a virtual device on the raspberry pi tho?