where can i find editional user information in my database in clear text?

Hello,
I'm trying to add additional information to my user when he wants to register on my website?
I used the following coding:
I added some input fields in the createUserWizard:
<tr>
<td>
                                <asp:TextBox runat="server"></asp:TextBox>
 </td>
</tr>

Code behind my page:
Protected Sub CreateUserWizard1_CreatedUser(ByVal sender As Object, ByVal e As System.EventArgs) Handles CreateUserWizard1.CreatedUser
  
Dim nGeb As ProfileCommon = ProfileCommon.Create(CreateUserWizard1.UserName, True)

        'Profielgegevens van nieuwe gebruiker aanpassen
     ...