I have a 1099-G for tax year 2020....what do I put in the box for total payments?

It depends.

Does your 1099-G indicate it is for tax year 2024?  You can locate the tax year it applies to in box 3 from your 1099-G form.  Assuming your 1099-G says 2020 in that box but was issued in 2024, you would enter the information based upon these instructions as it applies to your situation.

Where do I enter a 1099-G for state or local tax refund?

Where do I report a 1099-G for unemployment or paid family leave?

If however, the 1099-G was issued in 2020, you will need to amend your 2020 return to include these amounts. TurboTax does not support 2020 anymore. Please see this link for guidance on how to amend your return.  Please note if you are due a refund on this amendment, it is beyond the statute to receive any refunds due to you.

IRS - File an amended return provides additional details on the timeline to file an amended tax return for a refund.