Some apps are built in and pay to be on your tv. Those cannot be deleted. Any app that can be has the delete under the app in storage management. But don't worry Samsung provides you with parental lock settings simply go to settings then go to parental settings then go to parental lock click on app lock settings set up your pin and lock YouTube
6- Sixth step: Using the keyboard that appears on the Thomson 40FE5606 screen, type the name of the application you need to install. You can also use the remote control's microphone if you have one. Once you have written or dictated it, click on the “Search” button, it is the button with the icon of a magnifying glass that is located in the suxfMC.