I filed my taxes with a different provider before I finished them on turbo tax. Is it okay to leave them unfinished or can I cancel?

You should clear the tax return on the TurboTax account.

If you have not paid for the online edition you are using, have not filed your tax return or registered the Free edition, then you can clear your return. Click on Tax Tools on the left side of the program screen while working on the 2024 online tax return. Click on Clear & Start Over.