How to run Linux Mint as live usb always?

Question

USB

Hello.
There is a boot disk with a Linux Mint image, it can work as a live USB, but the problem is that when I start the PC, I have to manually choose what I want to do: either install (I can’t do this due to the lack of a hard drive), or run, or something else. I'd like to have Linux Mint run from a flash drive like a full OS and then start executing a couple of scripts.
Can you tell me if it is possible to configure it in such a way that it starts from a USB flash drive as an OS?

Answer 1

There are many variations:
1) INSTALLING LINUX ON A FLASH DRIVE
2) EDITING IMAGES IN LINUX
In general, the algorithm is as follows: unpack iso. Next, unpack the squashfs image (it is the largest). We mount file systems (system ones, like tmpfs, etc), then we go inside, and work as in a normal system. Update packages, install, remove, throw scripts into startup. Then exit the chroot, unmount the filesystems and pack the folder back into squashfs, and iso image (first you need to calculate the checksums of the files).