I am not sure of the relationship between your original data and the frequency table. Do you want to see how many times each value occurs in the original data, like this?
library(tidyverse)
DF <- tribble(
~tema1, ~tema2, ~tema3,
25, 6, 14,
25, 4, 11,
25, 2, 5,
11, 8,NA,
25, 6, 18,
2, 1,NA,
25, 6, 14,
21, 6, 4,
25, 6, 14
)
DF
#> # A tibble: 9 x 3
#> tema1 tema2 tema3
#> <dbl> <dbl> <dbl>
#> 1 25 6 14
#> 2 25 4 11
#> 3 25 2 5
#> 4 11 8 NA
#> 5 25 6 18
#> 6 2 1 NA
#> 7 25 6 14
#> 8 21 6 4
#> 9 25 6 14
DF <- DF |> pivot_longer(cols = everything())
DF
#> # A tibble: 27 x 2
#> name value
#> <chr> <dbl>
#> 1 tema1 25
#> 2 tema2 6
#> 3 tema3 14
#> 4 tema1 25
#> 5 tema2 4
#> 6 tema3 11
#> 7 tema1 25
#> 8 tema2 2
#> 9 tema3 5
#> 10 tema1 11
#> # ... with 17 more rows
table(DF$value)
#>
#> 1 2 4 5 6 8 11 14 18 21 25
#> 1 2 2 1 5 1 2 3 1 1 6
Created on 2022-01-14 by the reprex package (v2.0.1)