How to record whole process of flashing and stuff

I seen many videos where someone is able to record their screen from recovery all the way to the starting of a new rom etc. How can I do that. I am guessing I need my USB cable that is for sure. But what software would I need to carry out this whole process recording?

Any help is appreciated, Thank you..

TWRP Recovery Backup of whole system needed

Hi!
i have this HTC Desire 820u device that had some problems and needed a system flash.
when i dug into flashing it , i realized that actually no flash tool actually works with my phone! any efforts to flash this devices was a waste of time.
but one day i came up with a simple solution! using others TWRP Backups!! I managed to find a kitkat backup but it cannot be updated to 5 or 6 since the rom is not exactly made for my device. so if anybody could give me a backup i would appreciate the help:crying: