How do totally uproot weeds and keep them from coming back?

Sorry Peggy, that's not how nature works. Weeds are spread by wind, wildlife and people. Best we can do is control them. Where are your weeds? There are several methods to use depending on location.

We use pure white vinegar to kill weeds.

Hi Peggy, this works well. 1 gallon white vinegar, 1/2-1 cuo table salt. Mix together well and pour into a spray bottle and spray the weeds liberally. The dish soap will help the mixture to adhere to the plants a bit longer and let you know where you've sprayed. With a day they weeds will die and then begin to disintegrate. If not completely gone, repeat the process. Just don't spray the mixture onto plants you want to keep.

A neighbor had one weed in her yard she was not going to tolerate. Everyday she would look for them. She had a trowel and a plastic bag. She would dig up roots and all. Not let it touch the ground and put it in bag. After a couple of months she would only have to check once a week. Sometimes she would find one, mostly not.