I am attempting to find out what my income tax was for 2018 for FAFSA, but can not see my schedule 2 form on my tax return. Where can I find my income tax

Assuming the you have either paid the TurboTax online account fees with a credit card or have filed the 2018 federal tax return and it has been accepted by the IRS -

 

When you sign onto your online account and land on the Tax Home web page, scroll down and click on Add a state. 

This will take you back to the 2018 online tax return.

Click on Tax Tools on the left side of the online program screen.  Then click on Print Center.  Then click on Print, save or preview this year's return.  Choose the option Include government and TurboTax worksheets

 

Schedule 2 will only have Alternative Minimum Tax and Form 8962 Premium Tax Credit - https://www.irs.gov/pub/irs-pdf/f1040s2.pdf

 

Total taxes are shown on Form 1040 Line 15

Why do you need schedule 2?  Are you maybe filling out Fafsa?   If you don't have schedule 2 there is nothing to subtract from line 13.