How can I move a languge

For the past year, I have been using the english opencart and have built my site and filled it with all that I needed.
Most of my customers are arabic and have a hard time with english

I found an arabic version of opencart, but its for an entire site
I have installed in on a separate extension to try it out, and it works great with both english and arabic. The only problem is that all my data, settings, extensions and theme are on my mail english language site.
What I would like to do is to be able to just add the arabic into my existing and established site, and be able to set a separate theme for the arabic languge incase my theme doesn't support the right to left content. is that in any way possible by taking out files from the arabic version and moving them to my main site? and how would i do that.

If not, how can I move all my information and date to the new one in regards that the new one has 2 languages and not just 1?

so, No one can help me?

Pls will you tell me how you get and translate the site to arabic?
I am yet to reach that step.
Thank.