Get a soil test first.
If you don't have any other plants to save you can use weed killer. However, some of the tougher weeds may have to be treated more than once.
Water the weeds before you apply the weed killer and don't water for 24 hrs after. Weed killer works through the leaves so you want them plump. Follow all of the label instructions especially the precautions and mixing if you by a concentrate. Cover any plants you want to save with plastic so they won't be killed.
It may take a week or more for the deep rooted weeds to be killed and may take more than one application.
Remove the dead weeds. Till the soil, add amendments, compost, Big R , and whatever was recommended on the soil test and grade the area so that water will move away from the foundation and does not pool anywhere.
Water again. Weed seeds are not killed by post emergent weed killers. Water every day for a week. Spray again for any weeds that turn up. Keep repeating watering and spraying until no more weeds show up. Then you can put in the lawn. You may still have to weed but there should be fewer weeds to deal with.
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https://sod.com/html/weed_control.html
https://www.sunset.com/garden/garden-bas ... g-new-lawn
Happy gardening in Hawaii. Gardens are where people grow.