I would like to organize ~2000 subfolders by Country

I have a folder with a lot of subfolders starting with his country name in ISO Alpha-2 (US,GB,etc) i have made a basic bash script

#!/bin/bash
echo Folder name:
read country 
mkdir $country 
echo Prefix of folders:
read folder
mv $folder* $country
echo done

for organize but is quite exhausting one by one, I'm looking for a way to automatically do this, i guess that i will need a full country list but i don't know exactly how to do it.

You can use the find command to loop over all subfolders:

find . -type d -exec ./myscript.sh {} \;

This will pass the name of each folder path as variable $1 to the script. You can use the sed command to extract the relevant parts of the path from $1, e.g.

#!/bin/sh

country=$( echo $1 | sed -e 's/[^\/]*\/\(..\).*/\1/' )
remainder=$( echo $1 | sed -e 's/[^\/]*\/..\(.*\)/\1/' )

# There must be a remainder.
echo $remainder | grep '.' > /dev/null || exit
# Ignore subdirectories.
echo $remainder | grep '\/' > /dev/null && exit

echo "$1 => $country/$remainder"
mkdir -p $country
mv $1 $country/$remainder