WordPress is created two admin login URLs during WordPress standard installation. I am sure, you already know about this. These two admin login URLs are http://yoursitename.com/wp-admin and http://yoursitename.com/wp-login.php. If you want to improve your WordPress website security, then you must rename the default WordPress admin login URLs from wp-admin & wp-login.php to something else as you want.
It will improve your website security and protect your website from Protect Against Brute Force Attacks.
You ca re-write or rename your WordPress admin login URLs from default URLs to new URLs as you want using the .htaccess file. Open your .htaccess file from root directory of your website and copy paste below code at the end of the file.
RewriteRule ^admin$ http://your-website.com/wp-admin [NC,L]
RewriteRule ^admin$ http://your-website.com/wp-login.php [NC,L]
There are several WordPress plugins are available in WordPress plugin directory to rename your WordPress admin login URLs from default to something else. Rename wp-login.php is a very light plugin, which will help you to rename your WordPress admin URLs. Please bookmark your new changed admin URLs after changed new admin URL from default URLs because after changed, your wp-admin directory and wp-login.php page become inaccessible.
This plugin is also compatible with some popular WordPress plugins such as BuddyPress, bbPress, Limit Login Attempts, and User Switching.
The installation of this plugin is very easy like others. If you have just started with WordPress read: How to Install a WordPress Plugin. After installation of this plugin go to the Settings => Permalink and change the admin login URLs as you want.