How to display a text at the Windows 10 screen that appears always?

Question

I would like to display a text at windows 10 that needs to be always top up as windows 10 shows `Activate windows” when windows is not activated.

Is there any guidelines or documentation to get the work done?

Answer 1

In case you want a borderless window with transparent background, which is always on top:

<Window x:Class="MyProject.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="450" Width="800" WindowStyle="None" AllowsTransparency="True" Background="Transparent"  Topmost="True"
         >
    
    <StackPanel>
        <TextBlock Text="Activate Windows" FontSize="28"/>
        <TextBlock Text="Go to settings to activate Windows."/>
    </StackPanel>
</Window>