How to fit Windows Form to any screen resolution?

Docking can help of course. Just look in the Properties of the control how you want to be resolution independent and set the docking, then the control automatically resizes too when the form does.
For more please see this CP article;
Anchoring, Docking Properties of Controls in Windows Forms:
Working with Anchoring and Docking Properties[^]

Anchor and Dock Child Controls[^]
Anchor and Dock Child Controls[^]

Also have look on similar discussions, you will get surely needful from them:
Zom Out malfunctions when Screen resolution changes[^]
GUI Apperance - C#.Net[^]
how to dock button so that it can adjust with the form[^]

If you are using Winforms, then the chances are you can't do it with any real success - you can in WPF because it is very different.

However, in Winforms, just changing the size of a total form does not automatically affect the size of it's content - it can, if you have the Anchor and Dock properties set correctly, but even then, it doesn't affect the size of text in buttons, labels and so forth, so the resulting form can look very rubbish.

There is no real short cut. The best solution is to design the form to work with a minimum resolution, and allow teh user to scale up from that, rather than start with a maximum resolution and try to scale down.

Sorry, but I think you will have to do a fair amount of work!

Use the Scale method in the form load event. You will need to know the screen resolution of the computer you designed the form on. In your example, it was 1600 x 900. I set the initial resolution in a constant or a global config, but I used literal values here to keep the code simple. This will size the form and all child objects.

private void FormAutoResolution_Load(object sender, EventArgs e)
{
    // Scale our form to look like it did when we designed it.
    // This adjusts between the screen resolution of the design computer and the workstation.
    int ourScreenWidth = Screen.FromControl(this).WorkingArea.Width;
    int ourScreenHeight = Screen.FromControl(this).WorkingArea.Height;
    float scaleFactorWidth = (float)ourScreenWidth / 1600f;
    float scaleFactorHeigth = (float)ourScreenHeight / 900f;
    SizeF scaleFactor = new SizeF(scaleFactorWidth, scaleFactorHeigth);
    Scale(scaleFactor);

    // If you want to center the resized screen.
    CenterToScreen();
}

I suggest not to use Dock and Anchor properties. They are nightmarish.
1. Just leave the Anchor with top and left highlighted.
2. Get before screen size measurements by the following method:
AnteWidth = Me.Width and AnteHeight = Me.Height
You need to declare AnteWidth, and Anteheight or any other names as variables.
3.Get the current screen height and width measurements using the following method:
Dim screenWidth As Integer = Screen.PrimaryScreen.WorkingArea.Width
Dim screenHeight As Integer = Screen.PrimaryScreen.WorkingArea.Height
4. Calculate the width and height ratios as follows:
WidthRatio = screenWidth/AnteWidth and HeightRatio = screenHeight/AnteHeight

In the next step multiply the width and height measurement of each control with respective ratios.
Example: Button1.Width = Button1.Width * WidthRatio
Button1.Height = Button1.Height * HeightRatio
You need to assign new locations also to the controls that are next to the left most control. You will figure it out intuitively.
All this code must be entered in the form load area after keeping the form size to the minimum in order for the new display to occupy the screen completely. It is tedious but it works perfect.

You Can Use like this :-

this.windowstate = maximized

Use tablelayout control. It works for me.