The boot display failed to verify the digital signature of this file and failed to boot. Is it related to your improper operation before shutting down? For example: playing games, watching videos, operating big things, and using the computer for a long time caused by the card? Or download inappropriate things, or delete system files, or power off, etc., the fault will not happen for no reason, right?

press the power button to turn the machine on and off repeatedly. Try it for a while. You really can't reinstall the system. If you can't reinstall it yourself, it will take 3-5 yuan to find a maintenance person to help you.

as long as your computer doesn't get stuck, has a blue screen, and suddenly shuts down, it won't be like this when you turn it on.

please ask me if you have any questions.