2023 TurboTax Business is the correct product to use for filing a Form 1041 for an estate with an fiscal tax year that begins in 2023. It does allow you to specify fiscal year beginning and ending dates.
IRS Pub 559 says, "The estate's first tax year can be any period that ends on the last day of a month and doesn't exceed 12 months." March 2023 to March 2024 would be more than 12 months. Perhaps you could make the fiscal year April 1, 2023 to March 31, 2024 or March 2023 to February 29, 2024.
