I used to almost exclusively listen to any kind of audio through headphones. I had a microphone near my desk configured so that it would pass through the vibration of footsteps directly to my headphones. I was rarely startled, no matter what sordid activity I was undertaking.
By nature noticing these things repeatedly either comes from hypervigilance or having sensory differences that make you hear footsteps when others would not.
Obviously there are exceptions like if you live on a floor lower than someone or something.
I forget the type of mic but there are mics specifically designed for picking up vibrations from surfaces (I googled it, they're called surface mics ffs, could probably use a cheap normal mic without a pop filter tho)
If those use USB or 3.5mm, or can be made to, then plug them in and on windows check the "listen to this device" checkbox and boom, you'll hear what's coming through that mic. Adjust the sensitivity to your needs, done
On other OSs you can do it too just as easily but I don't remember what my Linux distro calls it and if you've installed Linux you have enough info from my comment to figure it out methinks