There are many books that try to help writers by giving plot formulas. Search for them.

Unfortunately, if you follow a formula, your story is apt to seems unoriginal, hackneyed, stale, and, of course, "formulaic."

The best way to develop an interesting storyline is to read hundreds or thousands of stories and decide for yourself what works best... and to write a story and ask other people to criticize it.

In my personal opinion, two writers who were very skillful at writing short stories were Jack London ("A Piece of Steak," "To Build a Fire," "Samuel") and O. Henry ("The Last Leaf," "The Gift of the Magi," "Springtime Á La Carte")

One very familiar device for creating a "page-turner" (a novel that makes you keep reading) is the "cliffhanger." You've probably seen it. It's common in thrillers and detective novels. The writer might follow two storylines at the same time, in alternating chapters, and end each chapter with a suspenseful situation.

End of chapter 5: "And then, to his horror, Biff saw the most terrible thing he had ever seen approaching."

Beginning of chapter 6: "Meanwhile, at the cabin, Rose was..."

A famous Hollywood story formula is "Boy meets girl, boy loses girl, boy gets girl."

A common pattern is a story that begins in a relaxed, everyday way ("Once upon a time, a woodcutter and his wife lived in the woods...") The reader is gradually drawn into a situation that becomes more and more complicated and dangerous. And then near the end, the story "resolves" with problems solved and questions answered: "And so, they lived happily ever after."

In my personal opinion, the British novelist Nevil Shute wrote novels with absolutely marvelous storylines. Some of my favorites are "The Trustee from the Toolroom," and "A Town Like Alice," and "The Chequer Board." (I do not like "On the Beach.")