The reason why you are not seeing the option found for "BitLocker is a full disk encryption" in Control Panel (even when you tried to search any drive) is that the Windows 10 edition that you might have bought was probably the Windows 10 Home edition and not the Windows 10 Professional edition or higher.
You have a two options that you can take from here.
- Pay $99 extra for Windows 10 Professional edition
- Use Veracrypt (free option and it is just as good as Bitlocker)
Here's how you can install VeraCrypt onto your Windows 10 computer
How to Install VeraCrypt
Step 1: Download and install
VeraCrypt.
Step 2: Just double-click on the
.exe file and follow the instructions in the wizard. Then select the
Install option.
I have written a quick step-by-step and easy to use guide for you (with screenshots and videos) to getting started with VeraCrypt and other alternative methods.
How to Enable Windows 10 Encryption (Fast & Simple)