Hi Tina, my name is Max and I'm an independent advisor.
I suppose you are using an old Windows 10 build because Telex Mode for Vietnamese keyboard is available for the latest Windows 10 build - 1903 May update and Windows 10 Insider Preview Builds (19H1) Build.
Please update Windows 10 to the 1903 version and you will start using Telex Mode for Vietnamese keyboard
https://support.microsoft.com/en-us/help/402766...
If you are unable to install the 1903 update using Windows Updates, please follow the instructions provided by PaulSey dated August 9, 2017 from How to perform an In-place Upgrade with Windows 10 Step-by-Step Guide
https://answers.microsoft.com/en-us/windows/for...
Once Windows update installed, perform the steps below to setup Telex Mode for Vietnamese keyboard on your PC.
- Go to Settings
- Time & Language
- Language from the navigation menu
- Select the + icon labeled [Add a preferred language].
- In the Search box, type in Vietnamese and click on it. Click on Next button and install Vietnamese on your device. You will be returned in the language page.
- Click on Vietnamese - Option - Language options: Vietnamese.
Click on the + icon labeled [Add a keyboard] > Enable the Vietnamese Telex keyboard or Vietnamese Number key-based keyboard.
On the taskbar, click on the input indicator button - Vietnamese Telex or Number-key based keyboard
