Here in the UK, guns are not banned as some Americans claim, but they are controlled and there are checks on people’s mental health. You are also not allowed to keep one loaded ready for use just in case. When not being used on a shooting range or on a farm, they need to be kept locked away and the ammunition also locked away separately.
That means we can’t react to someone breaking in my shooting them; not unless they choose someone who does have a gun and take such a long time to break in that the person in the house can unlock both gun and ammo and be ready for them.
But this isn’t really a problem. I have never been in a house that was broken into. The closest we came was when someone appeared to be trying to sneak around the back, probably to steal tools and garden equipment from a shed. As soon as our dogs, including a Rottweiler, barked at him he ran back to his car and sped off.
I don’t believe anyone would go to a house to burgle it and expect to have a fight with whoever lives there either with a gun or anything else. Burglars want to sneak in, sneak stuff out, and be gone again either when there isn’t anyone there or without waking up the occupants. That way they are not seen, not chased after and not caught so they get to do it all again another time. If they make a disturbance and wake people up, they risk people getting a good look at them and being able to describe them to police. Sooner or later, they would be spotted and arrested.
It would be foolish to go to a house and produce a gun to keep the occupants quiet. Especially if there are people in different rooms, someone will call the police and, if the burglar was armed, an armed response unit would be sent. The place would be surrounded by trained marksmen with no way out so the burglar will either end up shot or, if sensible and follows instructions, arrested and then facing a long prison sentence for having had the gun - much longer than for a normal burglary.