How can I: Copy a generic form and then make changes.

Why not just try it? In the amount of time it took you to provide additional information, you could have tried it. I appreciate the clarification. I also realize taht if you have not done a UserControl, it takes a little time to learn how to do it. It actually is very easy to do; you go to "Project | Add UserControl". Then add controls to the UserControl the same as a form. You might have to build the project, but then you can add the UserControl to a form by dragging and dropping the UserControl to the form.
 
Attached is a simple project I put together quickly. It is a proof-of-concept showing it is possible. If there is a reason that a UserControl does not satisfy your requiements, then I don't know what that is. I realize that you also might not know what you need that a UserControl does not do, so that is why it would help for you to learn about UserControls; it is time worth investing.

Hello Giorgio,i have an idea,let me know if it satisfies your requirements
you must have populated your form with usercontrols 
change the usercontrols modifiers from private to protected (you can see modifiers under usercontrol's properties) it unlocks the controls in the inherited form

hope it resolves your problem

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Sam:
 
I need to have a form that has some things pre-set, so I dont have to add them every time I want a new form. Some items are listed below:
 
Form size, menuStrip, toolStrip, statusbar, tabControl, groupBox... ands some labels and textBox.
 
I themwould want the option to change the above items and also add new items on the form.
Hope I explained it correctly.

It depends on what you need to do; what you need to modify and such. Also, will the form be used in the one project only?
 
Here is an important question. What does "change a few things in it" really mean? Will you add controls or do you need to change the way some controls work or do you need to replace some controls?
 
One possibility would be to make the form a UserControl. A UserControl can have multiple controls in it. Then you can add the UserControl to other forms. Depending on your requirements, that might be the easiest and most flexible solution.