Could someone please explain how do you make an opening line by introducing characters? Do you start with a 1st person's pov? Or 3rd? And like for example, what would your first sentence be?
Set the scene and have the character(s) doing something within the scene. For example, here are the opening lines of Stephen King's Salem's Lot. "Almost everyone thought the man and the boy were father and son. They crossed the country on a rambling southwest line in an old Citroën sedan, keeping mostly to secondary roads, traveling in fits and starts. They stopped in three places along the way before reaching their final destination: first in Rhode Island, where the tall man with the black hair worked in a textile mill; then in Youngstown, Ohio, where he worked for three months on a tractor assembly line; and finally in a small California town near the Mexican border, where he pumped gas and worked at repairing small foreign cars with an amount of success that was, to him, surprising and gratifying." Immediately, we get this: that the man is travelling across the country with the boy, and that they are not father and son. It also serves as a hook - why are they travelling together? What is their relationship? Where are the boy's parents? Why are they stopping so often and taking on odd jobs? Where are they going and why? Are they running away from something? It also includes a brief description of the man. He's tall and has black hair. That's really all we need. After this, their motivation is revealed bit by bit. It is hinted at in a conversation they have with a priest and then revealed as you read the book.
I usually show the point of view character doing something, mentioning them by name somewhere in the first couple of sentences. Here's an example from my current project.... Michael stepped through his front door, closing it carefully behind him. (Opening of chapter 4, Michael is the point of view character for most of this chapter)
Also, you can check out what other people have done by reading stories in the Workshop area of the forum. https://www.writingforums.org/workshop/
Is this appropriate for setting development? This seems more like character development or word mechanics.