gff/Pages/CustomerMenu.xaml

<Page x:Class="IS31Nabievv.Pages.CustomerMenu"
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
      xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
      xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
      xmlns:local="clr-namespace:IS31Nabievv.Pages"
      mc:Ignorable="d" 
      d:DesignHeight="450" d:DesignWidth="800"
      Title="CustomerMenu">

    <Grid>
        <Button Content="Переход 1" HorizontalAlignment="Left" Margin="320,203,0,0" VerticalAlignment="Top" Width="162" Click="Button_Click"/>
        <Button Content="Переход 2" HorizontalAlignment="Left" Margin="320,228,0,0" VerticalAlignment="Top" Width="162"/>
        <Button Content="Переход 3" HorizontalAlignment="Left" Margin="320,253,0,0" VerticalAlignment="Top" Width="162"/>

    </Grid>
</Page>