Bash – How to create multiple files names from list.txt in bash

Spaces in a file/directory name are fine as long as those names are properly quoted:

find . -maxdepth 1 -name "*.doc" | while IFS= read -r f; do 
    mkdir -- "${f%.doc}"; 
done

If you have to cd in and out of several directories then it makes sense to use cd - instead which takes you to the last current working directory. Or you use pushd / popd (in bash).

for directory in *; do
  pushd "$directory"
  index=1
  for filename in *; do
    extension="${filename##*.}"
    if [ "$filename" != "$extension" ]; then
      extension=".$extension"
    else
      # i.e. there is no dot in the file name
      extension=""
    fi
    target_filename="${directory}$(printf "%06d" "$index")${extension}"
    if [ -f "$target_filename" ]; then
      echo "File ${target_filename} exists; aborting."
      exit 3
    fi
    mv "$filename" "${target_filename}"
    ((index++))
  done
  popd
done

This code does not handle name collisions (if there is already a file Red00004) well. It just checks and aborts.