Set up Restrictions on Prime Video
Prime Video restrictions allow you to limit playback of content on Prime Video devices.
Fire TV devices, Fire Tablets, Fire Phones, and Microsoft Xbox 360 consoles have their own Parental Control settings.
Go to Account & Settings.
On the Prime Video app for Android or iOS, select My Stuff from the bottom menu, then select the Settings icon. From there, select Parental Controls, then Viewing Restrictions.
Select an age restriction and the Devices you want them to apply to, then click Save.
Note: Restrictions only apply to the device they were set up for.