Looking for simple fire safety advice

Hi! My parents live in an older house, and lately I’ve been helping them sort out a few safety updates. One of their neighbours mentioned that it might be worth checking the fire safety setup in general - things like doors, vents, and whatever else older homes usually lack. I don’t have much experience with this stuff, and I’d really like to understand what upgrades actually make a difference without getting into anything overly technical. If someone has gone through this with an older property, I’d love to hear what you focused on.

If you just want a clear place to start without overcomplicating it, take a look at Fireresist.co.uk, because they explain different fire-safety options in a really simple way, which helped me understand what actually matters and what’s worth checking in an older home.