I want to grow some fruit and veg at home... in my flat!

Yes, you can grow many different vegetables in containers - the big secret is giving them enough light. If you don't have a good window that will provide lots of sun for most of the day then you will have to get grow lights or something like that. I'm not sure about any fruits that will grow inside but am sure with enough sun there are some that could. You will also have to watch the temperature - some like it cooler while others won't produce without heat.

You most certainly can do it. I did tomatoes, bush cucumbers, banana peppers and bell peppers in containers this year. You don't really do anything different than you would if they were in the ground, you just have to be careful they don't dry out too fast. I started a lot from seed in the house and then transplanted outside, then planted some directly outside as the weather was warmer. I've got pictures of some of my vegetables in this discussion area.

i think its possible to grow orchids in flats, but what i heard about urban faming in japan is that it is possible to plant any plants in your plant, if u can search urban farming in internet u will get the answer

If you've got a well-lit area and/or are willing to supplement with lights, you definitely can do it! I've grown patio tomatoes and tomatillos in containers. Herbs also do brilliantly potted, and lettuces, spinaches, and other greens are excellent, easily kept veggies that you can grow containerized. If you seach for container vegetable gardening, you'll find tons of resources and ideas. Good luck!