[REQUEST] LDLC Mercure MH33-4SW

[arcadiabay]

Hello, first, thanks for this great forum.
There are so much useful infos here !
I need help concerning a laptop : LDLC Mercure MH33-4SW. It's quite unknown, looks like a chinese laptop. It's similar to a Jumper Ezbook 3 laptop : Intel N3350 CPU, 4  Gb of RAM, emmc of 32Gb (Sandisk DF4032)
My laptop has an AMI BIOS, its reference is HK-BI-14-Y116AR120-AA54V-02-G from 11/10/2017.
For now the bios is a really mess, but i'm suggesting a request not because of that... In fact i can not boot from anything else than Windows 10 (which is preinstalled). I would like to install Windows 7 and or Linux instead. The bios has no "Launch CSM" mod, so i have to boot only in UEFI i guess. I also tried to deactivate Secure boot, but without success : even if i see my usb key when trying to boot, i always had a black screen.
Furthermore in the BIOS, i have an option to select the OS (windows/linux), but if i change this parameter, the laptop does not boot anymore (no bootup screen).
I tried almost everything (enroll efi images on a linux usb key for eg) and i run out new ideas at the moment.
Could you help to tweak my bios in order to boot in BIOS mode (not UEFI) or do you know where i can download a bios which permit to do that ?
Thanks a lot

[jupiler]

Hello, since long time I was tought I am the only idoit on this planet buy this pc
There is no any support page for this pc on earth. I have one problem since long time when i turn on this pc screen doesn't show up. I need to power off and turn on again for get screen on. do you have that kind a problem with this pc?
Thanks