If issues are being experienced on certain apps such as the Camera app, or features such as Bluetooth then you can reset them following the steps below.
Option 1: Reset an App
1. Go to Settings > Apps & notifications > App info.
2. Select the App you want to reset.
3. Tap Storage and cache > CLEAR DATA > in the pop up window select OK.
The App you reset should now be useable without issues.
Option 2: Reset a Feature
1. Go to Settings > Apps & notifications > App info.
2. Tap the 3 dots at the top right > Show system.
3. Scroll down to the Feature you want to reset.
4. Tap Storage and cache > CLEAR DATA > in the pop up window select OK.
The Feature you reset should now be useable without issues.