The grass is too high for a lawn mower.

Borrow a string trimmer to get the height reduced, then mow it closely.

Cover the plot evenly with the cuttings, then cover it with several layers of newsprint or one layer of cardboard. Hold it down with rocks, bricks or whatever ...

Over the summer, add as much compost and mulch as you can find for free or cheap. It's better to cover part of the plot with 6 inches or so than skimpily cover the whole thing. So work on a section at a time as materials allow.

In the fall, plant in the section that was mulched first - dig right through the mulch and rotting paper layer. Keep amending the rest if you didn't finish it, and planting for a staggered harvest.

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In the fall, start a compost bin with dead leaves, weeds, and that sort of thing. Toss everything you can collect into it.

By next spring you should have a clean, well-amended bed with very little hard labor. And a good start on a compost supply.

Thankyou! Sounds like good advice.