macOS Bigsur: don't show the macOS install boot menu in OpenCore

hi, everyone.
My spec:
model name: H170-HD3
model: Gigabyte
bios date: 2016/11/03
CPU name: intel(R) Core(TM) i7-6700k CPU @4GHz
CPU id: 000406E3
Bios Version: F5

I tried to install the Hackintosh MacOS Big Sur on my pc using OpenCore, but I didn't.
1. I have setup OpenCore(0.79 and 0.76) in my USB using guide (https://Dortania.github.io/OpenCore-Install-Guide/)
2. macOS boot menu didn't show in booting. only show windows and restart/shutdown menu.

If you have the same case or...

Tonymacx86