It seems to me that the integer i should increase instead of decrease, and you would need to set a value for it at the start. (if you the output to look like what you said)
Uhm. No, it should decrease but the While condition was off, I think
Dim i, j As Integer
TextBox1.TextAlign = HorizontalAlignment.Center
'' clear the TextBox1.Text before you fill it with the *'s
TextBox1.Text = ""
'' Set the amount of *'s you want the first line to contain
i = 7
Do While i > 1
j = 1
Do While j < i
TextBox1.Text = TextBox1.Text & "*"
j = j + 1
TextBox1.Text = TextBox1.Text & vbCrLf
'' I would decrease i here, and not before the j-loop so that i indicates the amount of *'s in each line correctly
i = i - 1
I'd try it like that, hope this helped!
P.S. Don't forget the TextBox1.Multiline = True . I know I would lol
also, if something still goes wrong please tell us what error message you're getting/whatever.
Another Edit: if you want the first line to have 5 *'s, you will want to set i to 5, not 7 as I did