Preheat oven to 425°; place fries on a sheet pan, bake 10-12 min flipping fries halfway

Meanwhile, heat 1 tbsp oil in skillet over med-high; pat steak dry, season with salt/pep + sear undisturbed 2-3 min; flip + cook an additional 2-3 min for med-rare (for more well done add 1-2 min per side); rest steak 5 min

Add arugula to a large bowl; toss with lemon juice, 1-2 tbsp oil + salt/pep; divide everything between plates with 2-3 tbsp ranch per plate for dipping—tasty!