I had a vehicle loss due to a flash flood and my main transportation cost $10,000 additional dollars over insurance reimbursement to replace. How can I take a deduction?

If this was your personal use vehicle---not a vehicle used for business----and you are not in a federally declared disaster area, then sorry, there is nothing for you to enter about this on your tax return.   Casualty losses were eliminated as an itemized deduction by the tax laws that changed for 2018 to 2025, unless you are in a federal disaster area.