You need to activate i18n on your content type.
To do so, you need to go in the content type builder, click on the pencil icon next to the content type’s name, go to the advanced settings and check the “Enable localization for the content type” checkbox.
Then you can control the localisation of each field in the advanced tab of each attribute.
Here are some informations about the localisation:
- when i18n is enable on a content type all relational fields are localised
- the uid field will always be localised due to the unique constraint
- dynamique zones and components can be localised
- Unique fields must also be localised because of the unique constraint