I just completed one app in iPhone, now I wants to create same app for both iPhone and iPad.
I am new in iPhone, So don’t know exact what to do?
1) create the new project and select Universal option, and copy paste all code
2) modify this app for both.
How to add xib for iPad?

thanks
You are correct,
Select the Universal option.
Transfer code from the existing iPhone project to the new project.
NOW,
Make the xib files for iPad, and make the connections (IBOutlets).
Wherever you need platform specific features (eg. Popover, Split ViewController etc for iPad), put an
IFstatement to handle the device specific features.