There are several ways of finding a project in Crowdin you would like to participate in:
Visit our Showcases page where you can find a number of popular projects.
Before you start translating, some projects require a request to be approved. To submit a request, click Join. In the pop-up dialog, add some details why do you want to participate in that project.
If the project either does not contain the language you would like to translate into, there are some questions related to its content, or you would like to be promoted to a proofreader, you should contact the project manager.
On the project page, click Contact below the manager’s name.