After you file

Sorry not in the online version.  

The 1040SR is new starting in 2019.  It is the same as the regular 1040 just larger type and the Standard Deduction chart is added to page 1.  But has the same line numbers.    You automatically get the SR if you or your spouse are 65.  If you are using the Desktop program there is a way to force the one you want.

 

Compare them

1040SR  https://www.irs.gov/pub/irs-pdf/f1040s.pdf

1040   https://www.irs.gov/pub/irs-pdf/f1040.pdf

 

1040/1040SR Instructions  https://www.irs.gov/pub/irs-pdf/i1040gi.pdf

 

If you use the Desktop program you can switch to forms and the Info Wks part II has a selection to select 1040SR or not.  You can not change it in the Online versions.   In the Online version if you want to use the regular 1040 form, you can print out the 1040SR and copy the amounts onto the 1040 and then mail your return.