I got my 1099-INT from my Bank as every year. But this year, I got a 1099-INT form straight from IRS. What is this coming from? Do I have to upload both bank & IRS forms?

The form 1099-INT is to report the interest income that the IRS has paid you for paying your refund late. This is not your bank interest for which you will receive another form 1099-INT.

You have to enter the IRS form 1099-INT manually in TurboTax.  Choose I'll type it in myself.