Hi Jai,
Moumita is correct, you need to enable the multilanguage filter. But you must also have installed the Moodle language pack for the languages that you will be using. Finally, you will only see one language when viewing the page. In the Atto editor, you will always see both.
However working with the special HTML tags can be tricky for content creators and the content hard to understand when editing in the Atto editor since the tagging is not visible unless viewing the HTML code.
I suggest that you consider using the Multi-Language Content v2 instead. It uses {mlang} tags that you can just type right in the editor with your text. No HTML editing required.
For example:
{mlang en}Hello{mlang}{mlang fr}Bonjour{mlang}
You can also use it in a block mode like:
{mlang}
Many English paragraphs.
{mlang}{mlang fr}
Plusieur paragraphes en français.
{mlang}
Will display the word Hello or Bonjour depending on whether you are looking at Moodle in English or in French. As a bonus, the user entering the content will be able to easily see what text is tagged for use in what language.
As this is a 3rd party plugin, you will need to install and activate the filter. It is available from:
https://moodle.org/plugins/filter_multilang2
To activate, go to Site administration > Plugins > Filters > Manage filters > Activate "Multi-Language Content (v2)" and choose "Content and heading" as Apply to. This need only be done once to enable it throughout your site.
Now some activity types don't allow you to include content for more than one language, such as the file and URL resources. To work around this limitation, take a look at the Restriction by Language plugin from:
https://moodle.org/plugins/availability_language
It allows you to set an availability condition so that your activity only displays in a certain language.
As previously mentioned, not all themes include support for language filters. Even Moodle itself still has a few areas that don't go through filters before being displayed. However you should be able to see it work in the Boost theme on a page or in an HTML block. Test it there first. It it works there but not in your particular 3rd party theme or plugin, contact the developer and ask them to fix the issue. If they don't know what you are talking about, send them to this page:
https://docs.moodle.org/dev/Output_functions
...In particular, the format_text() and format_string() functions.
Hope you find this useful.
Best regards,
Michael
