Mourners prepared to gather on Friday in a corner of western Pennsylvania to say their final goodbyes to Corey Comperatore, the father of two who was killed during an attempt to assassinate former President Donald J. Trump at a rally last weekend.

The funeral was set to take place at 11 a.m. at the church in Cabot, Pa., where Mr. Comperatore, 50, was a longtime member. Afterward, a procession of fire trucks — as many as 500, some from as far as Florida and Texas — will travel from the church to the Buffalo Township Volunteer Fire Company in neighboring Sarver, where Mr. Comperatore served for decades.

Mr. Comperatore’s life revolved around this small pocket of Pennsylvania: He grew up in Sarver and still lived there with his high school sweetheart and two daughters. He attended church in Cabot and graduated from high school in nearby Freeport.

People here are not accustomed to crowds, but crowds are what they have spent the week preparing for as Mr. Comperatore has been thrust into the national spotlight.

A large electronic billboard above a road in Freeport displayed a photo of Mr. Comperatore, who Gov. Josh Shapiro said dived in front of his family to protect them as shots rang out. Next to his photo was a phrase that has been uttered by the governor and residents across Pennsylvania: “A Real Hero.”

On Thursday night, Mr. Trump singled out Mr. Comperatore during his speech at the Republican National Convention in Milwaukee, saying that he had “lost his life selflessly.” Mr. Comperatore’s firefighter uniform stood onstage near Mr. Trump as he spoke. At one point, the former president kissed the helmet and asked the crowd to observe a moment of silence for “our friend, Corey.”