Pictures?

Take a full-front overview of the whole yard, then smaller sections.

"Round up!" Spray everything! Vines are tough to get rid of. You can try dumping tons of boiling water in sections. That will cook the roots. It's a process, and you have to keep on top of it. We encountered the same thing! We still get suckers coming up and it's been over a year.

Found some amazing treasures in all the overgrowth and no dead bodies! Just a rabbit skeleton..........

There is hope. How do you eat an elephant? One bite at a time. Keep at it!

Truthfully, it is easier to lay down a thick well-overlapped layer of newspapers or corrugated cardboard over the native soil, then cover this with several inches of new screened topsoil or (if you recently won the lottery) of soil-less mix, such as pro-mix.

The newspapers/cardboard will eventually rot away, but before they do, the underlying weeds and vines will be killed. In the meanwhile, whatever you put on top of the new soil (or soil-less mix) whether it is grass seed or sod or annuals and perennials in a flower bed--whatever it is will have gotten a good start with no competition from the overgrown jungle.

A couple of things to watch for:
MOWING: Mow or string trim the existing vegetation until it's as LOW as it will go, before you start laying.
WATER:You have to frequently water ANY new planting into the new soil/soil-less mix. For the first year, the roots of the new planting will not penetrate the underlying newspapers/cardboard, so the roots will be shallow and will require more water than if they were growing in deeper soil. By the middle of the second summer, you can dial down the watering, but until then, you really do have to water more frequently. (I myself would rather water than weed, however, I live in Wisconisin, where water is not rationed).

If you are making a flower bed, you can cut down somewhat on the watering by adding a thick-ish mulch on top of the new surface, but for a lawn, you cannot mulch.

ENOUGH THICKNESS: For this trick to work, you need a LOT of newspapers or cardboard. You can probably get the amount you need at a recycling center, or by going around and collecting from your neighbors on recycling day. You want at least 6-8 sheets of newspapers over each spot, and at least 2-3 inches of overlap. Corrugated in a single layer is enough, but the overlap will need to be more as the cardboard is stiffer. Watering the newspaper/corrugated helps stop if from blowing away, and helps soften it to assist with conforming to the local bumpyness of the ground. But, lay soil on top asap, anyhow, because even quite wet newspaper will dry faster than you think and take flight at even a small wind.

AMOUNT OF SOIL: You want to add at least 1.5 inches, and 2" are better. This is a LOT of soil, so you might want to do this in sections, a little every day.

QUALITY OF THE NEW SOIL: If the new soil delivered is of low quality, you are simply trading one bad soil for another. If your local landscaper offers different grades of soil, get the one with most compost already in it. That way, even if weeds do get started, they'll more easily pull out of a loose and fluffy soil than a crusted low-organic- matter soil. Or, if you can afford soil-less mix (easier to afford for a flower bed than a lawn) you will have no weed-seed problem.

TIMING: Do all this AFTER tree-seed drop next spring, or you will be pulling out a million baby maples, elms, ash trees, whatever, out of your newly delivered soil. Some weed seeds will blow in on top no matter what you do, but by waiting until after tree-seed drop, you'll cut your weeding chores substantially.