I'm trying to import 3 rasters into R using

library(raster)
mytif <- list.files(path=my path, pattern =".tif$", recursive=T, full.names=TRUE)
s <- stack(mytif)

but it shows are 3 grids arranged horizontally and I want to arrange them vertically R shows my raster with 2025 rows and 3 columns, my desired result is 2025*3 rows and 1 columns!

I am new to R, I would like to know more about how to work with rasters