The question sounds like this

Permata store is a stationery store. It offers discount for every purchase as stated below.
Write a PROGRAM THAT CAN DISPLAY THE DISCOUNT OFFER, ACTUAL price, and price after discount.

        -Amount spent                Entittled discount
           50-100                       3%
           More than 100-300            10%
           More than 300                15%

Can you please help me on the interface and the code that needed....
Thank you, your help is really appreciated.

@Irahmiki - Please read the rules, one of which states

Do provide evidence of having done some work yourself if posting questions from school or work assignments

You didn't post your codes, so do not understand how far you wrote and the exception you got.

Reading your post I create a new like this 254e00b9460d092449ff6daffd5a5176

I suppose it would be solved your requirments
Codes are below.

Public Class Form1

    Sub initObjects()
        DataGridView1.AllowUserToAddRows = False
        DataGridView1.AllowUserToResizeRows = False
        DataGridView1.BorderStyle = BorderStyle.None
        DataGridView1.Dock = DockStyle.Fill
        DataGridView1.BackgroundColor = Color.White
        DataGridView1.GridColor = SystemColors.ActiveCaption
        DataGridView1.ColumnHeadersHeightSizeMode = DataGridViewColumnHeadersHeightSizeMode.DisableResizing
        DataGridView1.RowHeadersWidthSizeMode = DataGridViewRowHeadersWidthSizeMode.DisableResizing


        Dim x As String()

        x = {"50.00 - 100.00", "3", "1.50 - 3.00"}
        DataGridView1.Rows.Add(x)

        x = {"101.00 - 300.00", "10", "10.10 - 30.00"}
        DataGridView1.Rows.Add(x)

        x = {">300.00", "15", "45.15 and onwords"}
        DataGridView1.Rows.Add(x)


    End Sub

    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        Me.initObjects()
    End Sub

    Private Sub TextBox1_KeyDown(sender As Object, e As KeyEventArgs) Handles TextBox1.KeyDown
        'Restriction in inputting


        Dim intcnt As Integer

        'Count the charecter number after a Dot.
        'Chacking for two decimal places
        If TextBox1.Text.Contains(".") Then
            For i As Integer = TextBox1.Text.Length To 1 Step -1
                If Mid(TextBox1.Text, i, 1) = "." Then
                    Exit For
                Else
                    intcnt += 1
                End If
            Next
        Else
            intcnt = 0
        End If



        'Do somthing if appropriate key is pressed.
        Select Case CInt(e.KeyCode)

            Case 8         'For Backspace

            Case 33 To 40  'For nevigation keys

            Case 46        'For Delete key

            Case 48 To 57  'For 1 to 9

                If intcnt = 2 Then
                    e.SuppressKeyPress = True
                End If

            Case 96 To 105 'For 1 to 9 at Numeric Pad

                If intcnt = 2 Then
                    e.SuppressKeyPress = True
                End If

            Case 110       'For Dot

                'Check for the first character
                If TextBox1.Text.Length = 0 Then
                    TextBox1.Text = Chr(48)
                    TextBox1.SelectionStart = TextBox1.Text.Length
                Else
                    'Check for another pressing of dot
                    If TextBox1.Text.Contains(".") Then
                        e.SuppressKeyPress = True
                    End If
                End If

            Case Else : e.SuppressKeyPress = True  'For alphabates and others nothing to write

        End Select



    End Sub


    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        Dim disct As Double

        'Rejection for value < 50
        If Val(TextBox1.Text) < 50 Then
            MsgBox("No discount.", MsgBoxStyle.OkOnly, "Permata Stores")
            Exit Sub
        End If


        'If value >= 50 then calculate appropriate discount
        For Each nr As DataGridViewRow In DataGridView1.Rows
            Dim i As Integer = 0

            If IsNumeric(Mid(nr.Cells(0).Value, 1, 1)) Then
                Dim sx() As String
                sx = Split(nr.Cells(0).Value, "-")
                If (Val(TextBox1.Text) >= Val(Trim(sx(0)))) And (Val(TextBox1.Text) <= Val(Trim(sx(1)))) Then
                    disct = Val(TextBox1.Text) * Val(nr.Cells(1).Value) / 100
                    Exit For
                End If

            Else
                i = Val(nr.Cells(0).Value)

                If Val(TextBox1.Text) > i Then
                    disct = Val(TextBox1.Text) * Val(nr.Cells(1).Value) / 100
                End If

            End If
        Next


        'Display message for discount
        Dim x As String = String.Format("Dear Customer,{0}You get discount of {1} on purchase amount {2}.", vbCrLf, FormatCurrency(Format(disct, "0.00")), FormatCurrency(Format(Val(TextBox1.Text), "0.00")))

        MsgBox(x, MsgBoxStyle.OkOnly, "Permata Stores")
    End Sub

    Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
        Me.Close()
        Me.Dispose()
    End Sub
End Class

@Santanu Das - Daniweb is not a homework mill for people to get solutions when they are too lazy to put in the effort on their own. Posts of the type "I'm too lazy to do my own homework. Would someone please do it for me?" are to be discouraged.

@Santanu Das - Very thanks to you Santanu Das for the code
@Reverend Jim - I just want to ask questions for those who want to help new students like me and if you didn't want to help, please don't talk bad about the people because people learn from mistakes and smart people is people that asking questions because they're not arrogant to ask questions.

@mirahmiki - What part of

Do provide evidence of having done some work yourself if posting questions from school or work assignments

was unclear? Did you provide any evidence that you had put in any effort other than typing in the question? You didn't show us any part of an interface and you didn't post even one line of code. Please reread the rules.

This question has already been answered. Start a new discussion instead.