Entity framework MVC 5 and stored procedures without return data

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C#

MVC5

entity-framework

I am new to MVC and Entity Framework. I have the following stored procedure in SQL Server 2012:
-------------------------------------------------------------------------------

ALTER PROCEDURE [Elite].[AppInsertMrwdUpgrade] 
(
	 @UpgradeGrpID INT
	,@MrwdID VARCHAR(9)
	,@EID VARCHAR(10)
	,@ResultMsg VARCHAR(255) = NULL OUTPUT
)
AS

SET NOCOUNT ON;

	
SELECT DISTINCT TOP 1
	@ResultMsg = CONCAT('Marriott Rewards Number : ' ,@MrwdID, ' has already been succesfully upgraded to ', IIF(A.UpgradeLvlCd = 'P', 'Platinum' , 'Gold') , '.')
FROM Elite.MrwdUpgradeTranHist	AS A
	JOIN Elite.UpgradeGrpRef	AS B
		ON A.UpgradeGrpID = B.UpgradeGrpID
WHERE A.MrwdID = @MrwdID
	AND A.ResponseDt IS NOT NULL
	AND A.ResponseCd IN ('NO UPDATE LEVEL - LEV, LEV TYP & DT SAME','UPGRADE LEVEL LOWER THAN CURRENT LEVEL','NNIGN')
	AND A.UpgradeLvlCd >= B.MaxLvl
ORDER BY 1 DESC
;

IF @ResultMsg IS NOT NULL
	BEGIN
		RETURN
	END 
;

DECLARE @Lvl CHAR(1)

SELECT 
	@Lvl = R.MaxLvl
FROM Elite.UpgradeGrpRef				AS R
WHERE R.UpgradeGrpID = @UpgradeGrpID
;

INSERT INTO Elite.MrwdUpgradeTranHist
	(
		UpgradeGrpID
		, MrwdID
		, UpgradeLvlCd
		, InputDt
		, InputSource
		, UserID
	)
VALUES
	(	
		@UpgradeGrpID
		,@MrwdID
		,@Lvl
		,GETDATE()
		,'Manual_Assoc'
		,@EID
	)
;

SET @ResultMsg = CONCAT('Success! Marriott Rewards Number : ' ,@MrwdID, ' has been submitted for upgrade to ', IIF(@Lvl = 'P', 'Platinum' , 'Gold') , '.')
;

RETURN

-------------------------------------------------------------------------------
I want to be able to use MVC 5 and Entity Framework to call this stored procedure to insert a record if it is not a duplicate. I will use GroupID, MrwdID, and EID for textbox input with a submit button to activate the call of the stored procedure. I would expect to receive back the @ResultMsg and be able to either clear the form on success or keep the information in the text boxes for editing with a pop-up message to the user. (I realize some of this may be bad practices. We are using this on our Intranet only using IIS). I hope with what I have provided, a solution can be found.

What I have tried:

I have been able to create as Database first a Data Entity model which has identified both the stored procedure and function identified without a return collection. From there when I try to create a controller with view it errors saying there isn't an object.

I have tried with the associated table and it did create views. I used the Create View and modified it as follows:
-------------------------------------------------------------------------------

@model EliteMrwd.Models.MrwdUpgradeTranHist

@{
    ViewBag.Title = "Create";
}

<h2>Submit Upgrade</h2>

@using (Html.BeginForm()) 
{
    @Html.AntiForgeryToken()
    
    <div class="form-horizontal">
        
        <hr>
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.Label("Group ID: ", htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                <input type="text" id="UpgradeGrpID" name="UpgradeGrpID" value= @ViewBag.idName />
                @Html.ValidationMessageFor(model => model.UpgradeGrpID, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.Label("Marriott Rewards #: ", htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.MrwdID, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.MrwdID, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.Label("Submitting Person: ", htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => @User.Identity.Name.Split('\\')[1], new { htmlAttributes = new {@class = "form-control", @disabled="true" } })
                @Html.ValidationMessageFor(model => model.UserID, "", new { @class = "text-danger" })
            </div>
        </div>

         <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                
            </div>
        </div>
    </div>
}

@*<div>
    @Html.ActionLink("Back to List", "Index")
</div>*@

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}

------------------------------------------------------------------------------

My controller has the following sections of code:
------------------------------------------------------------------------------

public ActionResult Create(string id)
        {
            if (id == null)
            {
                ViewBag.idName = "";
            }
            else
            {
                ViewBag.idName = id;
            }
            return View();
        }
and 
       [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Create([Bind(Include = "TranID,UpgradeGrpID,MrwdID,UpgradeLvlCd,InputDt,InputSource,UserID,ExportDt,ExportCd,ResponseDt,ResponseCd")] MrwdUpgradeTranHist mrwdUpgradeTranHist)
        {
            //[Bind(Include = "TranID,UpgradeGrpID,MrwdID,UpgradeLvlCd,InputDt,InputSource,UserID,ExportDt,ExportCd,ResponseDt,ResponseCd"
            if (ModelState.IsValid)
            {
                db.MrwdUpgradeTranHists.Add(mrwdUpgradeTranHist);
                db.SaveChanges();
                return RedirectToAction("Index");
            }

            return View(mrwdUpgradeTranHist);
        }