to ATP and we love to help out beginning gardeners here!
First it would also help us to know what part of the country you are in. Your climate zone will dictate what you can plant and when. eg. I am in Florida so our season for planting cool season veggies is over already. Your broccoli, carrots, lettuce and radishes all need cool weather at least as they are starting out, to grow well. They will mostly even stand some very chilly nights, but if they get sudden hot days, some of them like the lettuce will 'bolt' and go to seed.
Second, as Jennifer said we need to know how big a 'box' you are building to grow your veggie garden in. Some veggies need a fair amount of space to grow properly, and are not suited for growing in a limited space. But as noted above, sometimes there are dwarf varieties that can grow in smaller spaces, so you might need to keep an eye out for those.
Be sure your box location has full sun for most of the day, and of course, a water supply nearby. Vegetables pretty much need to be watered every day. Also don't locate it too near any big trees. The root systems of large trees extend out at least as far as the branches reach, and if you situate a beautiful fertile raised bed on top of a tree's root system, then water it every day, the tree's roots will say "yummy" and totally take over the bed, sometimes in one season. Your veggie plants will grow beautifully for a while then you'll find them just dying off no matter what you do, and it's because the tree is robbing the soil of all the water and nutrients.
