Yes forging a check is a felony in all states.
When you forge a check you commit a serious crime that can get you jail time or prison time depending on the amount of the forged check and your past criminal history.
If the forged check is just the persons first offense then they may get off with 1 year in jail and a fine.
But if it's a second or third offense of forgery of a check then you may get 5 years in prison to as much as 15 to 25 years in prison.
Forging a check is never a good idea and so not worth the fines and prison time.
You will get at least some jail time for check forgery because of it being a felony.