Not necessarily. It depends on what the 1099-G would have been issued for:
State refund -- If you got a state refund last year AND you itemized your deductions, you will have to include the amount of the state refund in your return. If you took the standard deductions last year, then you don't have to include the refund.
Not all taxpayers will have this form. You will have it if you received a state tax refund or unemployment compensation, or certain other types of payments from the government.
If you received a state tax refund, but did not itemize your deductions for 2018 then you do not need to report the income and you can file without the form. You can also file without the form by simply entering the amount of the refund, if you do need to report it, and the name of the state that paid you.