Display Multiple Columns in Multiple Lines (MultiLine) in single TemplateField column in ASP.Net GridView

Here I have created sample that full-fill your requirement.

HTML

<div>
    <asp:GridView ID="gvCustomers" runat="server" AutoGenerateColumns="false" CssClass="Grid">
        <Columns>
            <asp:TemplateField HeaderText="Name">
                <ItemTemplate>
                    <asp:Label ID="Label3" Text='<%#Eval("name") %>' runat="server" />
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Info">
                <ItemTemplate>
                    Last Name:
                    <asp:Label Text='<%#Eval("lastName") %>' runat="server" />
                    <br />
                    Phone Number :
                    <asp:Label ID="Label1" Text='<%#Eval("phoneNumber") %>' runat="server" />
                    <br />
                    Address :
                    <asp:Label ID="Label2" Text='<%#Eval("address") %>' runat="server" />
                </ItemTemplate>
            </asp:TemplateField>
        </Columns>
    </asp:GridView>
</div>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[4] { new DataColumn("Name", typeof(string)),new DataColumn("lastName", typeof(string)),
                        new DataColumn("phoneNumber", typeof(string)),
                        new DataColumn("address",typeof(string)) });
        dt.Rows.Add("John", "Hammond", "8956898956", "United States");
        dt.Rows.Add("Mudassar", "Khan", "8956898957", "India");
        gvCustomers.DataSource = dt;
        gvCustomers.DataBind();
    }
}

Screenshot