Hi folks, hope you all had a good Christmas?

I'm wondering what is the correct way (as in where it should be done) to declare
and initialize my objects and variables in my classes? Should I declare and initialize all of them at the top of the class as in the following:

Code:
namespace An_Example
{
    public partial class Form1 : Form
    {

        //Declare and initialize here.
        //What would be considered a reasonable limit to the number  
        //of objects and variables declared and initialized here? 

        int myInteger = 10;
          
        Button myButton = new Button();

        List<String> myList = new List<String>();

        Object myObject = new Object();

        Etc, etc.

        public Form1()
        {
            
              initializeComponent();

        }

    }
}
Or should I use private methods later on in my code to initialize my objects and variables as in the following:

Code:
namespace An_Example
{
    public partial class Form1 : Form
    {

        //Declare, but don't initialize here
        //Should I use the keyword null?

        int myInteger = null; //Is this the correct way of doing things?

        int myInteger; //Or is this and the following examples the correct way?
          
        Button myButton;

        List<String> myList;

        Object myObject;

        Etc, etc.

        public Form1()
        {
            
              initializeComponent();

        }

        //Use private methods here to initialize my objects and variables. 

    }
}
Thanks for your help in clearing this up for me.