.htaccess on xampp for Windows

You need .htaccess on xampp for Windows.

Open a command line. Write there

C:\xampp\apache\bin>htpasswd -c -m -b c:\xampp\htdocs\.htpasswd username password

Create a .htaccess file and fill in it

AuthType Basic
AuthName "Access for restricted area"
AuthUserFile c:/xampp/htdocs/.htpasswd
require user username

Copy the .htaccess file to the directory you need the secured area.

Difference to your settings are: The path to the apache bin folder or htdocs folder on your xampp installation could be different. Change the above mentioned paths to your need.

The words "username" and "password" are only synonyms for real terms.