Add second language to new admin-module (modified oscommerce)

For a modified oscommerce webshop that already uses 2 languages, the second language needs to be implemented in a new module. The module displays text on a custom url: [login to view URL] [login to view URL] [login to view URL] ... For now it only displays the text in 1 language. There is also way to add a second language in the administrator. See screenshots. In other parts of the administrator, the language is already incorporated and working. I'm looking for someone to add the language in the admin module and make the text appear on the appropriate places on the website.