Just choose dwarf or small varieties of the plants you want to try. They usually may advertise about tomatoes or strawberries, but other small-fruit veggies would do fine.

I think beans would grow OK if they are on the top part.

Just know that your tomato will still try to grow upright so some people did tie it to make it point that way for a while, until more leaves or tomatoes were established that would naturally weigh it downwards.

The ones I tried came with just coconut coir as the soil component. It did let water soak through very easily and dry up fairly fast (as far as the plant is concerned), so I did have to water it fairly regularly.