I want to make changes to my 2018 return and it do not know how to open it. I went right to the end and paid Turbo tax already, but found out I can make other claims

 

After you file

As long as you have not NETFILED a tax return which reopens on February 18th, 2019, you are still able to make changes.  Simply log back into your TurboTax account, your return will be on the return manager screen.  You will then need to select it.  Use the following FAQ for instructions on how to jump around in your return, https://turbotax.community.intuit.ca/replies/3484165.