How can I make a payment page in my payment system ?

Question

I am working on an  payment system using mvc 5, And i almost finished a large part of the work such as the transfer of funds and the proportion of fees, etc.

But I'm having a problem now - the payment page for purchases from e-commerce sites,

And how a system api receives information from the customer, such as the price and account, and the name of merchant , That is, when the customer moves from the shopping cart to the payment page directly and the purchase information is converted to the payment confirmation page,

I tried to convert url information to the payment confirmation page but I did not succeed, and I hope to find help or code source  mvc5 with it and how to secure that page the transfer of this information.

 

 

public class Transaction
    {
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Id { get; set; }

        //foreign key of eBankingUser
        //hear userName will be assigned because GUID may not unique
        [Required]
        [Display(Name="User")]
        public string UserId { get; set; }

        //foreign key of transection table
       // [Required]
        public string OperationNumber { get; set; }


        [NotMapped]
        public string CountryName { get; set; }

        [NotMapped]
        public string CurrencyISO { get; set; }

        //[Required]
        public int? PinId { get; set; }
   //     public int? PinCode { get; set; }

        //Local amount that is inserted to transfer or recharge or top up
        public decimal? InsertedAmount { get; set; }

        //USD
        public decimal? AmountIN { get; set; }

        //USD
        public decimal? AmountOut { get; set; }


        public int? RatePlanId { get; set; }

        public int? Status { get; set; }

        public DateTime? TransactionDate { get; set; }


        [Display(Name = "Recepient User")]
        public string ToUser { get; set; }

        public string FromUser { get; set; }

        public DateTime? UpdateDate { get; set; }

        public string Remarks { get; set; }

        [NotMapped]
        public string ServiceName { get; set; }


        [Display(Name="Reference")]
        public string ReferenceId { get; set; }

        [NotMapped]
        public bool IsCheck { get; set; }
        public DateTime? TimeOut { get; set; }
        public bool IsTimeOut { get; set; }
        public int ClientId { get; set; }
        public int VendorId { get; set; }
        public decimal? UserBalance { get; set; }

    }

//Repository
 public bool CreditTransferDbEntry(Transaction tIn, Transaction tOut, string fromUser, string toUser)
        {
            ITransactionRepository transaction_repo = new TransactionRepository(db);
            using(var contextTransaction = db.Database.BeginTransaction())
            {
                try
                {
                    var fee = tren_rep.GetById(1).MRP; /*ConstMessage.ConstFee_ID;*/
                    tOut.UserBalance = transaction_repo.UserBalanceUpdate(fromUser, -(decimal)tOut.AmountOut);
                    transaction_repo.Add(tOut);
                    tIn.UserBalance = transaction_repo.UserBalanceUpdate(toUser, (decimal)tOut.AmountOut - ((decimal)tOut.AmountOut * ((decimal)fee /100)));
                    transaction_repo.Add(tIn);
                    //UserUpdate(fromUser);
                    //UserUpdate(toUser);

                    contextTransaction.Commit();
                    return true;
                }
                catch (Exception)
                {
                    contextTransaction.Rollback();
                }
            }

            return false;
        }