You can amend to complete the 2210 yourself or you can leave your return as is and let IRS calculate the underpayment penalty and bill you.
Please note the following information.
IRS does not require you to include a completed Form 2210 in your return.
If one is not included, then they will complete one for you and send you a bill for the penalty they say you owe.
If you do complete one with your return, they will generally accept the penalty calculated on it.
If it is included in your return, it gives you an opportunity to pay the underpayment penalty calculated along with any other balance due before the filing deadline and protect you from having any late paying penalties.
Per the Instructions for Form 2210 at irs.gov:
Use Form 2210 to see if you owe a penalty for underpaying your estimated tax.
The IRS will generally figure your penalty for you and you should not file Form 2210.
You can, however, use Form 2210 to figure your penalty if you wish and include the penalty on your return.
There are some situations in which you must file Form 2210, such as to request a waiver.
If you still choose to amend your return, please refer to the following linkS:
How do I add Form 2210 to my return
How do I amend my 2020 return
