Answer:
.Hello there! I would say you seem to struggle with sentence fragments, which is why it sounds so informal. On your first sentence you could say "The first setting of the story, the ranch, helped develop Eliza's character in many ways." That makes it sound more formal and less like a fragment of a complete thought. Then, you could explain what Eliza was like before she came to the ranch. Finally, mention how the stranger challenges her pre-conceived ideas of who she is.
In your second paragraph you struggle again with an undeveloped thought. Instead you could start with "Later, on the road, Eliza's character is further developed." Then you can stick to your same thoughts of how she became a stronger person. Try to avoid starting sentences with so or but, or using a lot of contractions (she've?). I hope this helps out a little!
