This article explains how to turn on Bluetooth on a Windows PC running Windows 10, 8.1, or 7.
How to Enable Bluetooth on Windows 7
Some computers offer a button or keyboard key that allows you to turn on Bluetooth with a single tap. However, if you can't find it, turn on Bluetooth in your computer's settings.
Select the Start button.
Type 'Bluetooth' in the search box and select Bluetooth Settings from the list.