3-tier Mvc application

Question

This code down here has errors when I run it in visual studio 2022. Kindly help out. I am quite new to MVC architecture
 
 

using System;  
using System.Collections.Generic;  
using System.Linq;  
using System.Text;  
using System.Data; // Required for using Dataset , Datatable and Sql  
using System.Data.SqlClient; // Required for Using Sql  
using System.Configuration; // for Using Connection From Web.config   
using BussinessObject;  // for acessing bussiness object class  
namespace DataAccess  
{   
    public class UserDA  
    {  
          SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["Myconstr"].ToString());    
        public int AddUserDetails(UserBO ObjBO) // passing Bussiness object Here  
        {  
            try  
            {  
                /* Because We will put all out values from our (UserRegistration.aspx) To in Bussiness object and then Pass it to Bussiness logic and then to DataAcess  this way the flow carry on*/  
             SqlCommand cmd = new SqlCommand("sprocUserinfoInsertUpdateSingleItem", con);  
                cmd.CommandType = CommandType.StoredProcedure;  
                cmd.Parameters.AddWithValue("@Name", ObjBO.Name);  
                cmd.Parameters.AddWithValue("@Address", ObjBO.address);  
                cmd.Parameters.AddWithValue("@EmailID", ObjBO.EmailID);  
                cmd.Parameters.AddWithValue("@Mobilenumber", ObjBO.Mobilenumber);   
             con.Open();  
             int Result = cmd.ExecuteNonQuery();   
             cmd.Dispose();  
            return Result;   
            }  
            catch  
            {  
                throw;  
            }  
        }  
    }  
}