If it's deleted, you can't retrieve it.
There's not one single place in TurboTax where you can enter your depreciable assets.
Rather, you'll need to re-visit your business, rental, farm, or job-related expenses, as appropriate. The program will the ask about related assets, and apply the relevant depreciation then.
With TurboTax Online open,
- Click the Pick up where you left off button, if it’s present
- Let the whole page load
- Click Federal in the left pane
- Type Income & Expenses at the top
- This should take you back to areas where you've reported income, and most likely would've entered depreciable assets.
Please see the TurboTax Help article Where do I enter Form 4562? for more information.