How to boot my own OS with CHUWI HI10 CWI529?

I had been installed ubuntu Linux 20 in my CHUWI HI10. (Already backup Windows 10)

The model is CWI529 Hi10 HQ64G42170700811

Before I using Windows 10 SwitchNOW.exe disabled the dual boot GUI.

But I cannot find any way direct boot into ubuntu. Everytime I need press F7 to boot the system.

I feel the problem is come form BIOS Locked boot method.

I want to know how to direct boot my own OS?

May I have a updated ROM for updated that issue?

Thanks

Anyone can help me please?