WPF DataGrid with dynamic cols

MainWindow.xaml

<Window x:Class="ControlsTestProject.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:ControlsTestProject"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <local:TableVm x:Key="ViewModel"/>
    </Window.Resources>
    
    <StackPanel DataContext="{Binding Source={StaticResource ViewModel}}">

        <local:MyTable />

    </StackPanel>
</Window>

MyTable.xaml

<UserControl x:Class="ControlsTestProject.MyTable"
             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:ControlsTestProject"
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">



    <Grid>
        
        <DataGrid x:Name="MyDataGrid" 
                  ItemsSource="{Binding Path=Rows}" 
                  AutoGenerateColumns="False"
                  CanUserAddRows="False">
            
        </DataGrid>   
    </Grid>
</UserControl>