'How to get and Bind() data from dynamic view in asp.net

I wrote Create() method to create a Test and I input that data- 1)choose from dropdownlist ,for which Course I want to add this Test 2)name 3)description I have issue when try to use method asp-for for dynamic model i do not know how use it correctly .For example, If i use Create(Bind("name, description,...")Test test) and in View =>asp-for="name"....asp-for="description" -> i get msg that i can not use asp-for dynamic

This is my Create() methods in TestController.cs


public IActionResult Create()
       {

           dynamic mymodel = new ExpandoObject();
           mymodel.test = new Test();
           mymodel.coursesChoose = courseService.GetAllCourses().ToList(); 
           return View(mymodel);
       }

       [HttpPost]
       [ValidateAntiForgeryToken]
       public IActionResult Create([Bind("name,description,CourseId,Course")] Test test)
       {
           //testService.AddNewTest(test);
           Console.WriteLine("///////////" + test.name + test.description + test.CourseId + test.Course.name);//returns null
           return RedirectToAction(nameof(GetAllTests));
           
       }

This is mu cshtml View

@{
    ViewData["Title"] = "Create";
    Layout = "_Layout";    
}

<div class="mask d-flex align-items-center h-100 gradient-custom-3">
    <div class="container h-100">
        <div class="row d-flex justify-content-center align-items-center h-100">
            <div class="col-12 col-md-9 col-lg-7 col-xl-6">
                <div class="CreateCourseForm card"  style="border-radius: 15px;">
                    <div class="card-body p-5">
                        <h2 class="text-uppercase text-center text-white mb-4">Create test</h2>

                        <form method="post" asp-controller="Test" asp-action="Create">
                            @Html.AntiForgeryToken()
                            <div class="form-outline mb-4">
                               <label class="form-label text-white" for="form3Example1cg">Course Name</label>
                            <div class="form-outline mb-4">
                                <select class="custom-select mr-sm-2" id="inlineFormCustomSelect">
                                    <option selected>Choose Course...</option>
                                    
                                    @foreach(Course course in Model.coursesChoose)
                                    { 
                                        <option CourseId="@course.id" Course ="@course" >@course.name</option>
  
                                    }
                                    
                               </select>

                            </div>
                            </div>
                            <div class="form-outline mb-4">
                                <label class="form-label text-white" for="form3Example1cg">Test Name</label>
                                <input type="text" id="form3Example1cg" class="form-control form-control-lg" asp-for"name" value="@testMod.name"/>

                            </div>

                            <div class="form-group">
                                <label class="form-label text-white" for="exampleFormControlTextarea1">Description</label>
                                <textarea class="form-control" id="exampleFormControlTextarea1" rows="4" asp-for"description" value="@testMod.description"></textarea>
                            </div>

                            <div class="d-flex justify-content-end">
                                <a class="CancelButton text-white" asp-area="" asp-controller="Test" asp-action="GetAllTests">Cancel</a>
                                <input type="submit" class="SaveCourseButton btn text-white" name="save" value="Save" />
                            </div>
                        </form>

                    </div>
                </div>
            </div>
        </div>
    </div>
</div>

Also there is my Classes. BaseEntity includes ONLY id