I filed my tax return and then I received a substitute 1099-g form. It says it's for tax year 2015 in the amount of $1034. I don't know why I got it or what do with it.

[AmandaR1]

That sounds like your state income tax refund, for when you filed your yearly taxes last year. If you didn't itemize your taxes and instead took the standard deduction, then you don't need to worry about this form. 

Itemized deductions include expenses like mortgage interest, property taxes, or large charitable deductions, so if you don't usually report these then you can know you took the standard deduction.