Back taxes

[Davong83]

I can’t file my taxes without 2018 taxes being done

[Critter]

Untrue ... although it is wise to complete the 2018 first in case you have anything that will carry to 2019 it is not required.   If you have not yet filed 2018 then simply enter a single ZERO for the 2018 AGI to efile the 2019 return. 

[JudyP2]

Previous is technically correct.  However, if the back tax returns that have W-2, 1099, etc. that they think you owe taxes on that year's return, the IRS will require you to file them before issuing a 2019 refund.  This means they will hold that refund to see if any of it is needed to pay any back taxes.