Can I Make a Bonfire Firm?

Could I put a bonfire into the cave and then also use control flames to make it double brightness to see if it like illuminates what's going on inside that cave before we enter it? Ooh, you could do that. You die from smoke inhalation. Re-roll character. Carbon monoxide poisoning. The cave entrances an arrangement of two large stalactites, two large stalagmites. It's kind of reminiscent of fangs in a yawning mouth. Does it say only a diamond in the rough can enter? Is that what it's doing? "I was thinking more Castle Grey's goal less Aladdin, but you know, that's cool"