I have some valuables in my home but nothing worth risking my life over. Likewise if I was walking down the street and robbed at gunpoint or driving in my car.
What I can I, in the situation of being subject to an armed robbery, do to increase my chances of not getting killed?
Ex-UK police (risk of armed robbery here is vanishingly low).
Comply. Just hand over what they ask for. Get a good look at their face/clothing (especially their shoes which are generally going to be unique and difficult to change whilst running away).
If you decide to fight back you risk getting beaten/stabbed/shot, then you’ll make a heroic victim, but you’ll still lose all your shit regardless.
If you’re in your home then arm yourself, barricade yourself in a room and call for help. Again, you can try and mount a defence but at the end of the day stuff and things can be replaced. Unless they’ve broken in with the intention of doing you or a family member physical harm then all you lose by hiding/escaping is a tv or a PlayStation.