Translating a project means, that all content items that are assigned to the project will be added to a translation workflow.
You can start a translation workflow for a project from the Control Room. Simply right-click the project and select Section 4.7.3, “Translating Content”.
from the context menu, or drag and drop the selected project onto Translation Workflows section. Alternatively, you can select content items in the Content link list of the project tab and start a publication workflow for these items. Proceed as described in