I have to determine the code on my small .htaccess for an additional.

Redirect url http://www.mydomain.com/somekw to http://www.mydomain.com/differentkw also http://www.mydomain.com/somekw?sort=rating&order=ASC to http://www.mydomain.com/differentkw

I've educate yourself about .htaccess however i have little abilities, hopefully someone can assist me.

This will work:

RewriteEngine on
RewriteRule somekw differentkw [L]

Which will change any demonstration of somekw of differentkw. The GET values will remain there.

Just make certain you've mod_rewrite enabled.