Our all Styled Themes support multi site including flat responsive. Our themes come with .pot file from which you can translate on any language. For this we refere you to use poedit. You can see this article for reference: https://make.wordpress.org/polyglots/handbook/tools/poedit/
File location
Hi,
I’ve find the file flat-responsive-pro.pot via ftp and I’ve installed on my pc Poedit.
What is the next step to do?
I believed that it was sufficient to install a plugin on my cms.
And then: on the site will show the flag with the languages to be selected from the user?
After creating .mo and .po file from poedit, you can activate your language from setting panel
Go to dashboard -> setting -> general ->on Site Language section -> you can choose your language
Excuse me but I need just that on the website which is online appear the flags of the languages and the user can select the desired language.
For the moment I want just do the preparation and later I proceed with translations.
How do I create .mo and .po file?
Ceceppa Multilingua plugin might help you. But plugin we had provide had good rating and more than 90000 download. So effective will q translate plugin. But still you can try by using ceceppa plugin.