If you closed your business in 2019 and still had inventory and assuming you were using COGS, then you simply report all remaining unsold inventory as "removed for personal use" and that's it. You're done with the inventory part.
If you did not use COGS but instead expensed the inventory, then for any left over and unsold inventory you must subtract what you paid for that inventory from your business expenses. It's not deductible if you did not sell it, donate it or otherwise dispose of it by some other means other than removing it from the business for personal use.
