2023 Tax Penalty

We have gotten a refund the last 5 years.  Last year it was close to $2K.  My husband started drawing SS in 2023 and we therefore we did not have to pull money from Retirment savings, which is heavily taxed.  So, this year we may owe over $7K in taxes.  We only have pensions, SS and Rental income.  The rental income is stable, but we had less rental property expenses.  How does the IRS calculate this penalty?