Keyboard input should 'just work'- you shouldn't have to do anything aside from plugging the keyboard in.
Quick example, starting from a blank UWP application:
XAML (Mainpage.xaml):
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<!-- Box to take user input -->
<TextBox Grid.Row="0" Grid.Column="0" Name="MyTextBox" Width="400"/>
<!-- Button to confirm input - note the Click event handler -->
<Button Grid.Row="0" Grid.Column="1" Name="MyButton" Width="60" Height="60" Content="OK" Click="MyButton_Click"/>
<!-- TextBlock displays text from TextBox on Button click -->
<TextBlock Grid.Row="1" Grid.ColumnSpan="2" Name="MyTextBlock" />
</Grid>
Codebehind/C# (Mainpage.xaml.cs):
public sealed partial class MainPage : Page
{
public MainPage()
{
this.InitializeComponent();
}
//Click event handler for MyButton
private void MyButton_Click(object sender, RoutedEventArgs e)
{
//Take the string value Text from MyTextBox (the user input) and assign it to the string value Text for MyTextBlock
MyTextBlock.Text = MyTextBox.Text;
}
}