it looks like there are some mature trees there. its hard to tell how much light reaches the ground. also like stated above, those trees are going to pull alot of nutrients and moisture from the soil. so you may have to prune the trees. thin out the canopy if thick. elevate the lower branches to allow more light to the area.
perform a soil test. figure out if the soil needs to be amended.
once you have a better feel for whether you can get a good stand of turf to grow, spray a straight glyphosate solution (roundup). id the various weeds to ensure you mix the correct % of solution based on the weed pressure. wait about a week, to allow the solution to work its way thru the shoots and the roots, then overseed. after the herbicide has had time to move thru the plant, then you can mow/weedeat down whatever is left. Glyphosate works best on actively growing plants, not ones which have been scalped to the ground and stressed out.