I never done taxes and I try doing it myself but I don't know if I transfer it to my 2020 W-2

What are you trying to do?

For 2019, you should follow the prompts in TurboTax to enter the information from your tax forms for 2019.  This would include W-2 forms for wages, 1099 forms for things like interest, dividends, etc.  It could include charitable deductions, mortgage interest reported on a 1098 form, etc.

I would recommend you go through each section of TurboTax (Income & Expense, or Deductions & Credits), scroll down to show more.  Review the sections to ensure you have reported the information from your forms.

When you get to the bottom of the income section, select Wrap up income.  This will take you to the next section.  Do this with each section to ensure you have picked everything up.

As long as you follow the prompts in TurboTax, you will be able to enter your information and the program will prompt you for more information if it appears you may be entitled to another deduction along the way.