Windows 10 has the least known feature called dynamic lock. This feature makes possible to automatically lock personal computer or laptop when you are away.
If you want to use dynamic lock feature, you need to pair your iPhone or Android phone to your pc. When your paired phone goes out of Bluetooth range, it will be automatically locked. The feature does not automatically unlock your PC when your phone comes back in the Bluetooth range. Dynamic lock helps you to keep your device safe when you are away.
Here is the way describing How to setup a Dynamic Lock Feature in Window 10
1- You need to pair your phone with your personal computer using Bluetooth, so in your phone turnon Bluetooth
2- On windows pc, navigate to Settings —-> Devices —-> Bluetooth and other Devices and here turn on the Bluetooth.
3- Next, you have to click on Add Bluetooth or other device option to see Add a device dialog.
4- Click on the Bluetooth option, your PC will now look for Bluetooth devices in its range. Your personal computer will find your smartphone in no time.
5- Once it finds the smartphone you have to follow the steps to add a device and pair with its code to your personal computer
6- Now since you have paired your phone with your pc, navigate to settings and go to accounts option from there you click on Sign in Option and in the dynamic Lock Section, turn on Allow windows to automatically lock your device when you are away option.
You can now check if the dynamic lock feature is working by moving your phone away from your personal computer properly or not.