if i uninstall the software that i just bought , can i reinstalling with a different language preset without pay anything ?

I can depend on what you just bought.

CS6 - You can swap languages/platforms for a latest version product if you follow the instructions at the following link:

http://helpx.adobe.com/x-productkb/policy-pricing/order-product-platform-language-swap.html

Creative Cloud - Change the language setting of your Creative Cloud apps