I am doing my taxes from 2018. I did not earn over $800 in 2018. I earned nothing during 2019 as I have been unemployed. am I using the right tax return 1040.

[DoninGA]

The TurboTax online editions are only for tax year 2020

If your only income from working as an employee was only $800 there is no reason to file a 2018 tax return unless you had taxes withheld and want a tax refund.  Or you had state Marketplace Insurance and received a Form 1095-A then you need to file. 

Or if your income was from self-employment then you are required to file a tax return.

To complete and file a 2018 tax return using TurboTax you would need to purchase, download and install on a personal computer one of the 2018 desktop editions from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/

A 2018 tax return can only be printed and mailed, it cannot be e-filed.

[xmasbaby0]

If you are trying to use the online program STOP.  Online is for 2020 returns only--no other year.

If you want to file a 2018 tax return for free use the paper forms and prepare them by hand.  It would cost you $80 to buy the software now.

2018 Form 1040, Schedules and Instructions

https://www.irs.gov/pub/irs-prior/f1040--2018.pdf
 https://www.irs.gov/pub/irs-prior/i1040gi--2018.pdf
2018 Tax and EIC Tables https://www.irs.gov/pub/irs-prior/i1040tt--2018.pdf

IRS 2018 Schedules 1 thru 6 (only if needed)
Sch 1 : https://www.irs.gov/pub/irs-prior/f1040s1--2018.pdf
Sch 2 : https://www.irs.gov/pub/irs-prior/f1040s2--2018.pdf
Sch 3 : https://www.irs.gov/pub/irs-prior/f1040s3--2018.pdf
Sch 4 : https://www.irs.gov/pub/irs-prior/f1040s4--2018.pdf

But----what kind of income did you receive in 2018?  Was it self-employment income?  Or did you get a W-2 with tax withheld that you are hoping to get back?  Why are you filing a tax return if you only had $800 of income that year?  Did someone else claim you as a dependent?  If you were someone else's dependent you are not going to get a stimulus check based on filing that 2018 return.