Skillet Roast Chicken with Fennel Parsnips and Scallions

Name: Skillet Roast Chicken with Fennel, Parsnips, and Scallions
Ingredients: 3 tablespoons olive oil, divided; 1 3½–4-lb. chicken; Kosher salt and freshly ground black pepper; 1 fennel bulb, sliced lengthwise ½” thick; 2 large parsnips, peeled, sliced ½” thick on the diagonal; 1 bunch scallions; 3 wide strips lemon zest; Lemon wedges (for serving)