the tax return you file for calendar year 2023 is a 2023 return. Your 2024 return would be for the calendar year 2024.
if you have qualifying assets that you put into service in 2023 you can take 179 depreciation on them (some may be subject to limitations) and you need net business income in excess of the 179 deduction. any 179 taken in excess of net business income becomes a carryforward to the 2024 return
