First timer after advice

Hey everyone. My garden is south facing and the flower beds below the hedges & trees receive zero sunlight all day. I’ve built a bit of a vertical planter for my garden and I’m hoping to grow the likes of some chilli peppers, spring onions and herbs to start with. I’m just wondering on the best location for it, I’ve seen mixed opinions on how much sun plants actually need. The attached video shows the 3 places that’d best suit the planter. Advice would be appreciated 👍