Insert multiple data in multiple tables using single ActionResult in ASP.NET MVC?

You can create a ViewModel which will have both the fields , signle values of form and list values of form.

Suppose You have two models of Blog and comments, so combining list of comments and on a blog model will be like below

public class BlogCommentViewModel
  {
      public BlogModel Blog { get; set; }

      public List<CommentModel> Comments { get; set; }
  }

Check this link https://www.codeproject.com/Articles/1108855/ways-to-Bind-Multiple-Models-on-a-View-in-MVC

Another solution(not preferred) :

You can submit two seperate forms (Single value and list value) on single button click using jquery/javascript using below function.

// new onsubmit function for form1
function form1_onsubmit()
{
    $('#form1 :input[isacopy]').remove();

    if (!EntryCheck()) return false; 

    $('#form2 :input').not(':submit').clone().hide().attr('isacopy','y').appendTo('#form1');

    return true;
}

In above code, we are  copying all of form2's inputs into form1 once the data validation check succeeds. This assumes you are not doing an AJAX submit, on controller you will get data of both forms.