I pd medicare premiums for 2019 out of my checking account $135.50 per month until I began receiving SS in October which was for September 2019?

You can enter them in 1 of 2 places ... 

1) on the SS entry screen ... simply add what you paid out of pocket to the amount listed on the form.

2) in the medical expenses section as insurance premiums

To enter your medical expenses -

• Click on Federal Taxes (Personal using Home and Business)
• Click on Deductions and Credits
• Click on I'll choose what I work on (if shown)
• Scroll down to Medical
• On Medical Expenses, click the start or update button

Or enter medical expenses, sch a in the Search box located in the upper right of the program screen. Click on Jump to medical expenses, sch a