No till setup

My family and I moved to a new house in late spring of 2023 that has a great place in the back yard for setting up a vegetable garden. It is on a retaining wall that is about 4-5' tall from the rest of my back yard as the entire housing development is situated on a hill. On top of the retaining wall I have 3 spots that are about 10x10 that I want to start my garden in. I tried going in last year and hand tilling up one of the sections and threw my back out in my effort. I was able to get some things planted, but by the end of July the entire plot was a mess of weeds and grass that despite my best efforts just took over. This year I am motivated to try again using a no till method for this space in addition to some grow bags I nabbed for cheap. Has anyone here done a no-till without making it a full on raised bed? The last raised bed I used was fine, but I am not as interested in making another one as I am just plopping some cardboard or newspaper down on the ground and adding compost and mulch on top to grow in.