I have a 1099G from 2016 how can I add it to this years taxes
You can not combine two tax year returns. You would have to amend your 2016 tax return to
include your 1099-G form for that year. Please see FAQ (click on see entire answer) and select 2016 tax year
for instructions for amending that return: https://ttlc.intuit.com/replies/3288565