If you don't have Kid Mode on your Samsung tablet. Then you can download it from Google Play Store. After downloading it, then follow the steps below to turn it on.
From the Home screen, tap Apps.
Tap Kids Mode.
Enter a new four-digit PIN.
Enter your child's name and birthday for their Kids Mode profile.
Tap Accept on the disclaimer.
Tap Skip to add apps to Kids Mode later, or Next to do it now.
Tap Finish