Languages
On the Crowdin home page are the all of the languages enabled for the MakeCode project. You go here first to choose the language or languages you wish to participate in for translation.
When you select a language, you see a folder view of the translation files for both the common parts of MakeCode and for each target editor. Each language has an identical folder view and the same number of files having the same names.
The source language for all of the files is English and that’s the language the files are in when uploaded to Crowdin. During the translation process, Crowdin keeps a database of all the current and suggested translations for each part of a translation file.
Target folders
Under each language there are top-level folders for all of the editors (including the MakeCode core) supported by the MakeCode team. Some of these are featured on the MakeCode home page. If you are interested in helping translate a particular target, you can focus your efforts in the files under its top-level folder. If you wish to help generally and want to work in more than one target, be aware that not all targets are presently active. To make your help count the most, you probably want to work with an active target. These are the active and inactive targets: