Hi,
you can display PLine and use Interactivity from NuGet. Try following demo:

XAML:

    <Window x:Class="Window052"
            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:WpfApp1.WpfApp052"
            xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
            mc:Ignorable="d"
            Title="Window052" Height="450" Width="800">
      <Window.DataContext>
        <local:ViewModel/>
      </Window.DataContext>
      <Canvas Background="White">
        <i:Interaction.Behaviors>
          <local:CanvasBehavior/>
        </i:Interaction.Behaviors>
      </Canvas>
    </Window>

And classes in VB.NET:

    Imports System.Threading
    Imports System.Windows.Interactivity
    
    Namespace WpfApp052
    
      Public Class ViewModel
        Public Sub New()
          Dim sc = SynchronizationContext.Current ' UI-Thread context
          ' asynchonously fill array vlues with data
          Task.Run(Sub()
                     Do
                       Thread.Sleep(20) ' 50 Hz
                       ' fill array with Y-values
                       For i = 0 To values.GetUpperBound(0)
                         values(i) = rnd.Next(1, 300)
                       Next
                       ' refresh polyline in UI thread
                       If CanvasView IsNot Nothing Then sc.Post(New SendOrPostCallback(AddressOf ShowValues), Nothing)
                     Loop
                   End Sub)
        End Sub
    
        Private rnd As New Random()
        Public Property CanvasView As Canvas
        Private pline As New Polyline()
        Private pointCollection As New PointCollection()
        Private values(99) As Integer
    
        Public Sub ShowValues(state As Object)
          If (CanvasView.Children.Count = 0) Then ' first Then Call, fill polyline And add To Canvas
            pline.Stroke = New SolidColorBrush(Color.FromRgb(60, 125, 200))
            pline.StrokeThickness = 1
            pline.Points = pointCollection
            For i = 0 To values.GetUpperBound(0)
              pointCollection.Add(New Point(i * 4, values(i)))
            Next
            CanvasView.Children.Add(pline)
          Else
            ' write New values in polyline
            For i = 0 To values.GetUpperBound(0)
              Dim pt = pointCollection(i)
              pt.Y = values(i)
              pointCollection(i) = pt
            Next
          End If
        End Sub
      End Class
    
      ''' <summary>
      ''' Behavior to get Convas in ViewModel (MVVM)
      ''' </summary>
      Public Class CanvasBehavior
        Inherits Behavior(Of Canvas)
        Protected Overrides Sub OnAttached()
          AddHandler AssociatedObject.Loaded, AddressOf AssociatedObject_Loaded
        End Sub
        Private Sub AssociatedObject_Loaded(sender As Object, e As RoutedEventArgs)
          CType(AssociatedObject.DataContext, ViewModel).CanvasView = AssociatedObject
        End Sub
      End Class
    
    End Namespace