You do not need to do an allocation between business and personal. Such an allocation would be applicable if you had sold a duplex where you lived in one half and the other was a rental, or if you had been renting out a room in your house. Since the entire condo was a rental, the business portion is 100%.
For the allocation between land and improvements, the best way to come up with that is to use the tax assessment. This allocation should also be done for the original cost basis. Let's say the total assessment for the condo was $100,000 allocated between land and improvements on your tax bill as $5,000 and $95,000. You allocate 95% of your purchase price and sale price to the improvements (which is the part you depreciate) and 5% to land (which you do not depreciate). Since it is a condo, as opposed to a single family house or a townhouse, it is probably not a fee simple property, which would mean you didn't actually own any land - just the condo unit. In which case the allocation between land and improvement would be moot.
For the amount of previous depreciation, that amount should equal the depreciation adjustment on Form 3115, not zero. That amount will be used to determine your cost basis, gain, etc.
As recommended in a previous answer, I recommend you seek some professional help for correcting the depreciation and reporting the sales transaction. TurboTax Live is an option, as is a local tax practitioner (CPA or EA) in your area. If it were me filing the return, I would file an amended return for 2022 with Form 3115 to adjust the depreciation. I would then file 2023 with the correct cost basis and accumulated depreciation to calculate the gain and depreciation recapture in 2023.
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