How to ACCESS IRS Form 5329 to Report Missed RMD, & APPEND my waiver request letter to my ONLINE submission of TT E-file?

We learned in January that one of our retirement investment firms had failed to send 2023 Required Minimum-Distribution in 2023. The firm admitted it was their error in a letter to her. I knowwe have to add the IRS Form 5329, the firm's letter, and our letter of explanation/request for waiver.  
But HOW do we access, complete & append the 5329 & our letters on to our TT e-file, to summit our return electronically to IRS?
My wife and I are 76 years old.  
Sincere thanks for anyone's kind help!