How to make permanent storage on a flash drive in Linux?

Question

linux

I put a friend on a Linux Mint flash drive. The screw was taken from him for repair for 2 weeks, so I came up with this way to get out so that the computer would not be idle. Mint - because familiar with Linux in general in any way.
The question arose of how to make user data be saved in a file on the same flash drive, as is done, for example, in Linux Pappy? So even the live system is loaded, but the user data is loaded every time, and saved every half hour.

Answer 1

I was rescued in such a situation - www.pendrivelinux.com - this is live usb, but with the ability to save documents and install applications (what was called live usb with persistent storage above)