If you purchase potting soil, I would ask someone on staff at a nursery or garden center. If you want to mix your own, here is a PDF about growing vegetables in containers: http://aggie-horticulture.tamu.edu/publications/guides/e-545_vegetable_gardening_containers.pdf
Most of these vegetables are very easy to grow and hardy. The peppers may need some kind of special care, not sure. I haven't grown any of those myself. The other four in the pack are growing in pots and doing nicely.