Weed killers need to be handled with care both to get the best results and to avoid accidents. Glyphosate is probably the most widely used garden weed killer these days.
Originally only sold under Monsanto’s Roundup brand name but since patents have expired it is manufactured by many companies and sold under many brands.
Below is a useful video from Australian “Greg The Gardener” demonstrating how to get the best out of using Glyphosate for weed control. I had not heard of adding washing up liquid to the mixture to help the spray coat shiny leaves before.