To prevent the wingtips and drumstick ends of a chicken from burning, tuck the wingtips under the chicken's body and, for drumsticks, you can loosely tent them with small pieces of aluminum foil, especially during the latter part of roasting.
The wingtips and drumstick ends of a whole chicken are thinner and contain less meat compared to the breasts and thighs, making them susceptible to overcooking and burning before the rest of the chicken is done. To address the wingtips, a simple and effective technique is to tuck them under the chicken's body before roasting. This position shields them from the most direct heat, preventing them from crisping too quickly or burning. Many trussing methods for whole chickens automatically incorporate this step. For drumstick ends, especially if they are particularly bony or thin, you can loosely cover them with small pieces of aluminum foil once they've achieved a desirable golden-brown color, typically halfway through the roasting process. This foil acts as a shield, deflecting direct heat and allowing the rest of the chicken to catch up in cooking without the ends becoming charred. Remove the foil for the last 10-15 minutes if you want them to crisp up further.
If you notice any part of the chicken browning too quickly, you can always loosely tent that specific area with foil for the remainder of the cooking time.