Thanks for your indications ! I haven't done anything yet, but in a couple of hours I'll start with the following:
- Create a UEFI bootable Ubuntu Live USB
- Boot into the Live system
- Install partimage
- Create a backup of the entire drive
With that, I should be safe from any other stupid mistake in the future
But I was looking the serial number and it got me confused because it is: Q64G45170401720 (it seems newer than the ones in the instructions) so I'm a bit scared
On the other hand, I had this idea: maybe it would be possible to get the original Android partitions from someone and then create the corresponding partitions in the drive myself and just copy them there, but clearly that would require some source... Or would it be possible to do it manually from the Android image ?
I know it's possible to extract the content of the Android image and do some modifications on it, it's just an ext4 partition (system.img) with some quirks but the size of each partition would need to fit and I don't know them
I also noted that the problem for flashing a new Android is due to the fact that the UEFI BIOS is trying to boot into 64-bits, and the Android image only contains a 32-bits binary, hence the "bootx64.efi" is not found, but maybe that file exists inside the image itself, if not, then inside the Windows 10 image. It has to be somewhere because the system would not boot otherwise (unless the Android-IA option in the BIOS is related to the 32-bit mode...)
I'm willing to test all those assumptions, but a bit of extra help would be really helpful
In any case, thank you very much !!