first page script
<asp:TextBox id="txtName" runat="server" />
<asp:LinkButton ID="LinkButton1" OnClick ="Btn_Click" runat="server">testLink</asp:LinkButton>
first page code
protected void Btn_Click(object sender, EventArgs e)
{
Response.Redirect(string.Format("~/Default2.aspx?name={0}", txtName.Text));
}
for get query string valueon second page load event add
Label1.Text = Request.QueryString["name"];