@AmeliesUncle is correct based on your original facts which indicated that you had no income OR expenses.
As a result of not doing this in 2020, which technically should have been the case, you need to make sure that your Sch C does reflect any depreciation as that would be incorrect.
Hopefully marking 1/1/2021 as you indicated, does not give you one day of depreciation. Just make sure it is zero.
Also, keep in mind that you step into the shoes of the assets tax basis, and upon sale, you will be required to report any depreciation recapture.
*A reminder that posts in a forum such as this do not constitute tax advice.
Also keep in mind the date of replies, as tax law changes.
