Yes vinegar and salt does kill weeds.
You can mix some vinegar and salt together in a spray bottle that is undiluted and then spray the weeds with the vinegar and salt solution.
The vinegar and salt solution will kill the weeds within a day or so but can sometime take longer and you may need to spray the weeds again with the vinegar and salt but it will kill weeds.
To make the vinegar and salt even more effective at killing the weeds you can add some dawn dish soap to the vinegar and salt solution to kill the weeds.
The Dawn dish soap, vinegar and salt solution will kill the weeds much faster.
It's a natural weed killing solution that is better for the environment than using other weed killers such as Roundup.
Roundup does work great though but it's not cheap and can be harmful to your health and the environment.