In TT, how to add the form for First Time Abatement?.
How to delete the form that charges the penalty?
(TT charged me underpayment of estimated taxes. My employer withheld less tax).
You don't. If you underpaid your tax, regardless of the reason, you owe a penalty.
Not true. see this information https://www.hrblock.com/tax-center/irs/audits-and-tax-notices/tax-dictionary-first-time-penalty-abatement/
The article you shared explains that you will need to contact the IRS in order to request the First Time Abatement. There is no form to file to make the request.
Because you are requesting an abatement of the penalty, the form calculating the penalty should be filed with your return. If the request with the IRS is accepted, then your return would be adjusted accordingly.