How do i fill out form 8863

If you are asking how to get to Form 8863, in TurboTax Online, all forms generation is based on the interview questions.  

When you complete the questions in the applicable section, using Form 8863 as an example, you will answer the questions in the Education section and if you qualify for education or other credit, the Form 8863 will be generated and be included in your return when you file.

To get to that section of the software follow these steps:

After sign in,  select Take me to my return/ 

 1.  At the right upper corner, in the search box,  type in education expenses, then Enter.

2.  Choose the 1st choice Jump to education expenses on the search results /

3.  The program will take you directly to Did you want to enter your higher education expenses?  Select Yes and continue to follow the onscreen instructions.

In the Desktop version of the software, you can click on "Forms" to view a particular Form.

Here is a link to the IRS blank form if you needed to see a pdf of the form:  Form 8863

If you were asking where to get your Form 1098-T, you will need to obtain that from your University.  Most will have it available through online access.