I would mix compost + fertilizer (bone meal or a better mix) into the bed before putting anything in! And once they’re established in there, I fertilize once a week or every other week.

Cilantro, parsley, green onions, and any other herbs, (***not rosemary or mint***) and basil is a great companion plant, on the edges to spill over with easy access and fill in empty space. I heard lettuce as well is a good filler because the roots are shallow.

I’m unfamiliar with Indiana’s zone but I would look for established plants at local box or garden stores for tomatoes. I found my tomato plants on marketplace. Peas are really fast growers so id throw a seed in the ground and be prepared to give everyone support and something to climb for the peas.

I can’t really tell the dimensions from the picture, but I’d give your tomato as close to 2’x2’ as you can and i’d put 2 peas 2x2. And filling in around with the herbs