Much of the film was shot in Canada with the field being located near a bowling alley which was featured in the film. The church, however, was a temporary set made for the film on site.
There is a 1959 Chevrolet sitting outside the church with its grille customized to resemble Christine, the 1958 Plymouth from Stephen King's novel with the same name.
A character speaks of turning left or turning right in "this garden of forking paths." "The Garden of Forking Paths" is a 1941 short story by Jorge Luis Borges that speculates about taking turns left or right in a winding, branched garden leading to different points in space, time, and possible outcomes. This is a common theme in Borges' work, and very much fits in with events in the movie.
Patrick Wilson stepped in for James Marsden, who departed the project to do Sonic the Hedgehog (2019).
If you look carefully, the stained glass in the church looks like grass.