add a row of dummy text to data frame

for reasons that have to do with checking an error in ArcGis, where my data is going, I need to add a row at the top that contains dummy variables, which I would like to be Column1:Column(n)

For example, I have this:

  ID A  B    C
1  A 1  8 set1
2  A 2  9 set2
3  B 3 10 set1
4  B 4 11 set2
5  B 5 12 set3
6  C 6 13 set1
7  C 7 14 set2

I would like this:

       ID       A       B       C
1 Column1 Column2 Column3 Column4
2       A       1       8    set1
3       A       2       9    set2
4       B       3      10    set1
5       B       4      11    set2
6       B       5      12    set3
7       C       6      13    set1
8       C       7      14    set2

I understand that this would make some numeric columns into character. Some dummy data from dput is below. As a note, my real data set has many more actual columns.

dput(df)
structure(list(ID = c("A", "A", "B", "B", "B", "C", "C"), A = c(1, 
2, 3, 4, 5, 6, 7), B = c(8, 9, 10, 11, 12, 13, 14), C = c("set1", 
"set2", "set1", "set2", "set3", "set1", "set2")), class = "data.frame", row.names = c(NA, 
-7L))

>Solution :

With tidyverse, use add_row after converting the columns to character

library(dplyr)
library(tibble)
library(stringr)
df %>% 
 mutate(across(everything(), as.character)) %>% 
 add_row(!!! setNames(str_c("Column", seq_along(.)), names(df)), .before = 1)

-output

    ID       A       B       C
1 Column1 Column2 Column3 Column4
2       A       1       8    set1
3       A       2       9    set2
4       B       3      10    set1
5       B       4      11    set2
6       B       5      12    set3
7       C       6      13    set1
8       C       7      14    set2