There is no Form 4265. Do you mean Form 4562 for depreciation? To enter depreciation you have to enter whatever you are depreciating as an asset. If you tell us what version of TurboTax you are using, someone will be able to give you more specific instructions. Are you using TurboTax Online or the CD/Download TurboTax software? What edition are you using (Deluxe, Premier, etc.)?
Also see the following FAQ.
Where do I enter Form 4562?
