When you launch TurboTax you should see the screen "Continue your 2018 Tax return" and under it the tax return you were working on with a "Continue" button (if you saved the return when exiting last time). Click on the "Continue" button and it should bring you to the area you last worked on. If not then you can navigate by using the tabs on top. You mentioned you just finished the income section if you like to review this section you click on "Personal Income". If you like to continue with the next section click on the tab "Deductions &Credits".
When you launch TurboTax you should see the screen "Continue your 2018 Tax return" and under it the tax return you were working on with a "Continue" button (if you saved the return when exiting last time). Click on the "Continue" button and it should bring you to the area you last worked on. If not then you can navigate by using the tabs on top. You mentioned you just finished the income section if you like to review this section you click on "Personal Income". If you like to continue with the next section click on the tab "Deductions &Credits".