iOS Restrictions is build for the use case when you want to restrict usage of phone features when someone else is using your phone. It is very useful for example to restrict “In-App Purchases” while your kid is using your phone for some games.
You can however use Restrictions for yourself by hiding unused system apps from the home screen. For example to reduce web browsing time or you use primarily other browser, you can hide Safari. If WhatsApp or Facebook Messenger is your video chat apps, you can hide the FaceTime app. Or hide the Podcasts app and use one from third party developer. Sometimes disabling “In-App Purchases” for yourself is a good choice when self-control is not enough.
To use it, go to Settings app > General > Restrictions. Tap “Enable Restrictions” to switch it on, and iOS will prompt you for a passcode to access this settings.
Simply turn off the switch to disable the feature you want. Not all Apple apps are available for you to disable. If you like your home screen tidy, go ahead and hide some unused apps and features.