You will need documents for any distributions that were taken from your Health Savings Account (Form 1099-SA) or retirement accounts (Form 1099-R). You do not need any documents for a health care FSA.
If you did not take any distributions from the HSA or retirement accounts, then everything you need might already be included on your W-2. The W-2 will show any HSA contributions made through payroll deductions and also contributions to retirement plans that were funded through payroll deductions.
If you made any additional contributions to your HSA or a retirement account (IRA), then those will need to be entered as part of your return as well.
In almost all cases these days you do not need to upload any documents. If you do TT will let you know.
For the most part you either type in or import the need info, answer TT's questions, and electronically transfer your return to the IRS.
The folks who provided your with the information returns (1099's, etc.) will send that info to the IRS (typically electronically). If the two amounts don't match the IRS will let you know (eventually). Some data the IRS doesn't get. In the unlikely event that you are audited you will need to be ready to provide documentation to support every number you have entered on your return.
If that wasn't what you meant, please clarify or ask again.