Translation Workbench lets you specify languages you want to translate, assign translators to languages, create translations for customizations you’ve made to your Salesforce org, and override labels and translations from managed packages. Everything from custom picklist values to custom fields can be translated so your global users can use all of Salesforce in their language.
Note: Translation Workbench isn’t available for single-language orgs.
From Setup, enter Translation Language Settings in the Quick Find box, then select Translation Language Settings.
On the welcome page, click Enable.
Click Add, specify the Language, and identify translator users for the language.
2- Translate Components
To get started in the Translation Workbench;
From Setup, enter Translate in the Quick Find box, then select Translate.
Select a language (if you’re a translator for more than one language).
Select a setup component, for example “Custom Fields”
If necessary, select an object and aspect. For example, Account File and Field Label.
Double click in the translation column to enter new values. You can tab to jump to the next row.