Like this?
library(dplyr)
df <- tibble(x = c("1500000 5kkkkk22222", "000 abcde bb11111"))
df
#> # A tibble: 2 x 1
#> x
#> <chr>
#> 1 1500000 5kkkkk22222
#> 2 000 abcde bb11111
df |> mutate(a=substr(x,1,2),b=substr(x,3,11),
c=substr(x,12,17),d=substr(x,18,100)) |>
select(-x)
#> # A tibble: 2 x 4
#> a b c d
#> <chr> <chr> <chr> <chr>
#> 1 15 "00000 " 5kkkkk 22222
#> 2 00 "0 abcd" e bb 11111
Created on 2022-01-30 by the reprex package (v2.0.1)
Edit with better code.
library(dplyr)
library(stringr)
df <- tibble(x = c("1500000 5kkkkk22222", "000 abcde bb11111"))
df
df |> mutate(a=str_sub(x,1,2),b=str_sub(x,3,11),
c=str_sub(x,12,17),d=str_sub(x,18,-1)) |>
select(-x)