library(tidyverse)
# replace this with whatever you're interested in
str <- letters
set.seed(1)
tibble(what = sample(str, 25),
       row = rep(1:5, 5),
       col = rep(1:5, each = 5)) %>% 
  mutate(what = ifelse(row == 3 & col == 3, 
                       "Free space", what)) %>% 
  ggplot(aes(row, col)) +
  geom_tile(color = "black", fill = "white") +
  geom_text(aes(label = what)) +
  coord_fixed() +
  theme_void()