Windows 10: Help. My old LenovoG470 just got a blank black screen with a underscore not blinking

it was lenovog470 running on windows 11 server and while installing it I use setupprep.exe in the iso but this is just the details here's the problem.I was playing games raging out cause it's lagging so bad and I didn't know much anything until I trying to overclock my laptop using... Advanced bios and I did change something on the bios well. I thought old laptop can overclock until now I know I need to use the uefi bios to overclock cpu to make the laptop or PC runs faster than my Wi-Fi at 3 am. Can anyone help me fix this thing it was a windows 11 server it doesn't boot up and I think I just

:)

 

Black screen with a blinking underscore

I turned my computer on yesterday and it has been displaying a black screen with a blinking white underscore on the top left corner.

 

My screen turns black with blinking underscore

So i was going to play some games on my gaming windows 10 pro pc and when i turned it on there was a black screen with a blinking underscore please help

 

Blinking underscore and black screen on boot.

I left my laptop to update overnight then I woke up the next day and turned on my laptop then when it booted it showed a blinking underscore and a black background. Please help quick!