Dynamic Keybinding?

Any ideas on how to fulfill this logic?

OnButtonClick(){

//Wait for user keypress
//Capture keypress
//Save keypress for later keybinds

}

I'd like for the use to be able to press any button(Most buttons works too) but I need mouse buttons to work.

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I've looked @ some stuff involving getch()? But got very confused and information was diluted.

if((GetKeyState(VK_LBUTTON) & 0x100) != 0)