grub2 - Problem with boot Ubuntu on Acer Aspire V15 Nitro (Black Edition)

I have Acer Aspire V15 Nitro (Black Edition) with UEFI on Windows 10. I installed Ubuntu alongside Windows 10. I followed all the instructions explaining how to configure it to work.
It means:

• quickstart off
  


• security boot disabled
  


• set in cmd grub as the boot loader (bcdedit /set {bootmgr} path \EFI\linuxmint\grubx64.efi)
  

By default, Windows 10 starts every time.

Finally, GRUB 2 does not start by default. To enable ubuntu I have to perform a breakneck mission. DO I start the computer, quickly click F12 (boot menu), it opens and I see:

1. Windows Boot Manager
   


2. Windows Boot Manager

enter image description here

By trial and error I finally clicked 2. and GRUB started ... Only this way I can enable Ubuntu.
GRUB ukrywa się pod "2. Windows Boot Manager"

While the bios menu looks like this:
enter image description here

I would like to start GRUB by default. Any ideas?