On an installment agreement with the IRS for federal taxes owed from previous years. Will the installment payments made in 2019 have an impact on my 2019 tax liability??

No.  Each year is separate.  If you have a refund they will keep it for any past due you owe.

No.  The installment payments you have been making are for a past year (or past years)  They have nothing to do with any tax you owe for 2019.  If you are getting a refund for 2019, though, the IRS will take your refund to pay toward the back taxes you still owe

The money you paid to the IRS for a previous year’s federal tax return is not deductible, so you do not enter it anywhere on your 2019 return.  If you paid taxes due in 2019 to your state or local government, you can enter that by going to Federal> Deductions and Credits> Estimates and Other Taxes Paid> Other Income Taxes.  You can enter the taxes you paid, but do not include any penalties or interest.

There are six states that allow you to enter the federal tax you paid on your state return--Alabama, Iowa. Louisiana, Missouri, Montana, and Oregon.  If you are filing in one of these states watch for the deduction when you prepare your state return.