Advice on removing artificial grass

We bought a house last month, and one of my favourite aspects of it is the garden. It’s a fairly decent size, south-facing and seems like it would be perfect for my very first gardening project. It has artificial grass down and I’m desperate to pull it up and start some real grass. I would also like to add some raised beds to grow veg, fruit and herbs. I pulled up a corner and dug around – there’s a layer of sandy soil, then some medium sized gravel, a membrane of some sort and finally what I believe is the original soil – which is a moist, clay type of soil. I have no idea where to begin! Would I need to remove everything up untill the clay soil and then fill it up with ??top soil before planting my grass? I’ve never had a garden before and it’s all a bit overwhelming but I have a vision in my head of a wildlife-friendly, fertile and veg-filled garden! Please help me get there. 🥺