How to create DLL files for all the classes in an application while they have an internal relationship with each other?

Question

I created a test project. I have two classes as follows:

class1:

namespace ConsoleApp1
{
    public class calc1
    {
        public double num1 { get; set; }
        public double num2 { get; set; }
        private double _num1 { get; set; }
        private double _num2 { get; set; }
        public calc1(double num1, double num2)
        {
            _num1 = num1;
            _num2 = num2;
        }

        public double Multiply()
        {
            return _num1 * _num2;
        }
    }
}

class2:

namespace ConsoleApp1

{
    public class calc2
    {
        private static double _input;
        public double input { get; set; }
        public calc2(double input)
        {
            _input = input;
        }

        public double Calculate()
        {
            calc1 c = new calc1(_input, _input * 2);
            return c.Multiply();
        }
    }
}

Program.cs:

using ConsoleApp1;

calc2 c = new calc2(12.3);

Console.WriteLine(c.Calculate());

Now, I want to create dll files for each of those classes. How can I create DLL files using a class library project? What is the best solution for creating DLL files for each class in a project and avoiding a single EXE application?