Create a property on Form2 that saves the value you wish to pass into a private variable, call the property before showing the form.
Fr the example below Form1 would say Form2.Setb = b to set the b value.
Public Class Form2
Private b As Decimal
Private d As Decimal
Public WriteOnly Property Setb As Decimal
Set(value As Decimal)
b = value
End Set
End Property
Public WriteOnly Property Setd As Decimal
Set(value As Decimal)
d = value
End Set
End Property
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Label1.Text = (d + b).ToString
End Sub
Alternatively create a public global variable on Form2 and set it directly.
Public Class Form2
Public b As Decimal
Public d As Decimal
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Label1.Text = (d + b).ToString
End Sub