Mix chicken with paprika, half of the olive oil, half of the garlic, half of the salt, and half of the pepper together in a bowl until evenly coated. Toss potatoes with remaining olive oil, garlic, salt, and pepper in a separate bowl; add lemon slices and toss well.
Arrange chicken in a roasting pan and surround chicken with potatoes and lemon slices.
Bake in the preheated oven for 25 minutes; rotate and flip chicken and potatoes. Continue baking until chicken is no longer pink in the center and the potatoes are tender, 20 to 30 minutes. An instant-read thermometer inserted near the bone should read 165 degrees F (74 degrees C).