How to insert a textblock that is in the combobox for database in SQL server C# uwp

I have an accept button that is the one that saves the data for the database.  I wanted to know how I can insert the ComboBox options

private async void BTAccept_Click(object sender, RoutedEventArgs e)
        {
            string rbRiesgo;
          try
            {
                const string SqlString = "insert into AllergyTable(DuoDate,PetName, Category,Risk,Treatment,Note)values(@duoDate,@petName,@category,@risk,@treatment,@note)";

                 using (SqlConnection conn = new SqlConnection(connectionString))
                {
                    

                    conn.Open();

                    if (conn.State == System.Data.ConnectionState.Open)
                    {
                        using (SqlCommand cmd = conn.CreateCommand())
                        {
                            
                            cmd.CommandText = SqlString;
                            cmd.Parameters.Clear();

                            cmd.Parameters.Add("@duoDate", SqlDbType.Date).Value = DateAllergy.Date.Value.LocalDateTime;
                            cmd.Parameters.Add("@petName", SqlDbType.VarChar, 40).Value = txtnombre.Text;
                            cmd.Parameters.Add("@category", SqlDbType.VarChar, 40).Value = cbCategoria.Text;
                            
                            

                            

                            if (RBBajo.IsChecked == true)
                            {
                                rbRiesgo = "0";
                                cmd.Parameters.Add("@risk", SqlDbType.VarChar, 20).Value = RBBajo.Content;
                            }
                            if (RBMedio.IsChecked == true)
                            {
                                rbRiesgo = "1";
                                cmd.Parameters.Add("@risk", SqlDbType.VarChar, 20).Value = RBMedio.Content;
                            }
                            if(RBAlto.IsChecked == true)
                            {
                                rbRiesgo = "2";
                                cmd.Parameters.Add("@risk", SqlDbType.VarChar, 20).Value = RBAlto.Content;
                            }


                            cmd.Parameters.Add("@treatment", SqlDbType.VarChar, 50).Value = txtTratamiento.Text;
                            cmd.Parameters.Add("@note", SqlDbType.VarChar, 50).Value = txtNotas.Text;


                            cmd.ExecuteNonQuery();
                            conn.Close();

                            MessageDialog Md = new MessageDialog("The record has been inserted");
                            await Md.ShowAsync();

                        }
                    }

                }
            }

            catch (Exception ex)
            {
                var Msg = new MessageDialog("Exception:" + ex.Message);
                Msg.Commands.Add(new UICommand("Close"));

            }

        }

<ComboBox Margin="10,20,0,0" x:Name="cbCategoria" SelectedItem="{Binding Item,Mode=TwoWay}"  Width="180">
                            <ComboBoxItem IsSelected="True">
                                <TextBlock x:Name="txtAlimento"   x:Uid="Alimento" Style="{StaticResource TextTextStyle}"/>
                            </ComboBoxItem>
                            <ComboBoxItem>
                                <TextBlock x:Name="txtMedioAmbiente"   x:Uid="MedioAmbiente"  Style="{StaticResource TextTextStyle}"/>
                            </ComboBoxItem> </ComboBox>

I have entered in the line of adding for Combobox the database selectItem, Text etc.

cmd.Parameters.Add("@category", SqlDbType.VarChar, 40).Value = cbCategoria;