Boot Loaders deleted, How to restore EFI?

I accidentally deleted (Don't really know how) all of the boot entries that appeared on efibootmgr on a laptop that had no operative systems (I did it from an Ubuntu Live USB).

Now, when i try to start the computer, it says 'Boot Device Not Found, Please Install an Operating System on your Hard Disk' and it wont even boot from a CD/USB with Windows/Ubuntu.

I tried changing the boot order from the BIOS Settings, disabling secure boot and legacy boot, and reverting to default settings, but nothing seems to work.

I'ts my fault for touching things i dont know enought about, but... Is there any way to Fix this?

The laptop is an HP if it matters.

Thank you.