where will i put? How? Please help, I am new to photoshop.
The installer will prompt you when you install Photoshop. That's when and where you input your s/n.
Since that is such a basic question, I feel obliged to gently point out that if what you have is Ps Elements, rather than Photoshop proper, you really want this other forum:
Community: Photoshop Elements | Adobe Community
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