Walk to the door and open it.
From Create Your Own Story
Dr. Dero rushed towards the brown door and set a cold hand on the doorknob. Slowly, he turned it.
The door flew open and slammed against the sides of the... cave?
Dr. Dero stepped out of the door. A black, dark cave overlooking a beautiful forest. "What in the heck?!" Dr. Dero exclaimed. He stepped to the entrance of the cave. A split line of trees in the median of the hill stuck out at the entrance of the cave. It was obvious now: Dr. Dero could go left, or go right.
Left appeared to head into the darker side of the forest, which could be plentiful with animals and fruit.
Right appeared to lead to the forest streams and rivers, which could provide water but be considerably more hectic of a path.