Go to left route and start walking
From Create Your Own Story
You decide to go left and walking. You keep walking until you find many big tree. You decide to rest for a night as the moon is start glowing.
Suddenly, you heard a little voice from one of the tree. You look at it and find many caterpie is there. You decide to caught one of them. You throw a pokeball to the caterpie.
After a little shake, the pokeball click. You got a new pokemon for your team.
Next day, you boost your way and get to Truck City!