Question Critical - Help Needed: Acer Aspire V5-571 No UEFI/Legacy Boot Menu or Secure Boot option

Feb 4, 2020
I am trying to clean install Win 10 on Acer V5-751 but whenever I come to 'Windows Setup' Drive allocation - format, delete, new section it says 'Windows can't be installed on this drive - The selected disk has an MBR partition table. On EFI systems, Windows can only be installed to GPT disks'.

I figured it was due to BIOS being in UEFI mode, so I have tried to change it to Legacy and disable 'Secure Boot' like on other laptops/bios. But unfortunately, I cannot find UEFI/Legacy Boot menu or Secure Boot disable/enable options on Boot tab of this specific Acer laptop. But only see Boot priority order sub-menu.

So I googled, youtubed everything I enable that option. Most suggestions say I have to set a Supervisor password on Security tab which I did and hit F10 to save and restart back to BIOS and it would show. But it didn't Also I have already enabled F12 Boot menu option in Main tab. Also I have used Rufus to create both GPT and MBR bootable usb flash win 10 but both doesnt work. Thus I have no idea how to install Windows 10. Please see attached photos and advice me how to make this work. Thank you, much appreciated.