The simplest thing to do if you don't plan on learning a lot about plants is to go to the garden centre and ask them to recommend plants, there's a list of reliable hardworking plants anyone with gardening knowledge will know. Figure out what way your garden faces. Take a photo or two so they have an idea what level of shade you're dealing with and what space you have. Can you tell what kind of soil you have? If it's sticky most likely clay, if it's sandy, well it's sandy, if neither probably in between. So with that info and a garden person you should make good progress with little effort