soal

The password for the next level is stored in the file data.txt, where all lowercase (a-z) and uppercase (A-Z) letters have been rotated by 13 positions

solve

cat data.txt | tr '[A-Za-z]' '[N-ZA-Mn-za-m]'
# The password is 7x16WNeHIi5YkIhWsfFIqoognUTyj9Q4

flag

7x16WNeHIi5YkIhWsfFIqoognUTyj9Q4