Dual booting linux on ROG STRIX G531GT despite heavy screen flickering on startup/BIOS/BOOT MENU

[brainstormer]

I have an asus rog strix g531gt.
I want to dual boot to linux, but my screen flickers on startup and nothing is visible(I cannot see anything on my screen due to the flickering(on startup/BIOS/BOOT menu)). I can try installing the linux distro via a VM, so as to not shut down my laptop and not face the flickering, but how will I boot into whatever OS I want to? Can anyone with the same laptop list the key combos required to:
1) Switch between different OSes(windows, linux etc.) on startup
2) Launch into the boot menu on startup
3) Launch into the BIOS menu on startup
Alternatively, can anyone suggest other ways to install linux on my HDD without shutting the laptop down?
PS: I have a temporary fix for the screen flickering, and that is to lower my refresh rate to 48hz and if that doesn't work, connecting the laptop to an external display via an HDMI cable does the trick. However, the HDMI trick does not work when the laptop is starting up/on the boot menu/BIOS etc.

[brainstormer]

can a customer service guy please answer?

[Anbby_ROG]

Hi @brainstormer ,

Unfortunately, since the G531GT laptop does not come with a pre-installed Linux operating system, we are unable to provide specific technical support for Linux. If you encounter any issues related to Linux, we recommend referring to Linux-related websites for assistance in resolving the problem. Thank you for your understanding.

[brainstormer]

that is an extremely bad and unhelpful answer
I'm asking for the specific keybinds to install linux on my system, if I am unable to see the screen. Also, I would like the keybinds to switch b/w windows and linux once it is installed(these keybinds are specific to the laptop model, ie. rog strix g531gt). Chatgpt gave me a better response than you.