can someone explain why TT says I have Underpayment Penalties when my taxes are taken out every two weeks and paid by my emplyer

If you do not have enough withholding from your employer, or have additional income during the year, you may incur the penalty for underpayment of estimated taxes.  

See Underpayment Tax Penalty - TurboTax Support - Intuit

Maybe based on the W-4 you gave your employer, not enough was withheld to cover 90% of 2024 taxes or 100% of 2023 taxes. 100% becomes 110% if your 2023 adjusted gross income was $150,000 or more. Review the 2210

some ways underwithholding can occur. irregular paychecks. income not subject to withholding and not properly accounted for when preparing the W-4.