Do not try to enter your SSA1099 or RR1099RB as a W-2. Go to Federal> Wages & Income>>Retirement Plans and Social Security (SSA1099 and 1099RRB) to enter your SSA1099.
Your 2019 Form 1040 can include three possible extra schedules (for 2018 there were six!) Here is what Schedule 3 looks like:
https://www.irs.gov/pub/irs-pdf/f1040s3.pdf
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