Is it safe to bake a frozen whole chicken without thawing it first? How long/At what temperature?

If you don't thaw it first, it will be charred and dry near the outside by the time the inside is cooked. You should thaw it. Thaw it in a refrigerator for a couple days, or if you need to thaw it faster, put it in a bowl under cold running water. Do not thaw it at room temperature - that is unsafe.