How to type caste IEnumerable to an object list using lameda expression and foreach loop

           List

o1= new List

();

           
           var output = db.TaxOnProduct("Chai", 2, "Beverages").ToList();
           List

o1 = output.Select(x => new Output { CategoryName = x.CategoryName.ToString(), ProductName = x.ProductName, TotalAmountAfterTax = x.TotalAmountAfterTax, TotalBeforeAfterTax = x.TotalBeforeAfterTax }).ToList();

           foreach (var test in output)
           {
               Output objoutput= new Output();
               objoutput.ProductName = test.ProductName;

               o1.Add(objoutput);
           }

i used entity frame work and get data using store procedure then used lameda expression to put output in list of object