Is there a reason you'd need to do so? What is freetaxusa.com missing that direct file gives you (other than the fact that direct file is free and supported by the government itself)?
also, you need to submit selfies and have a usa sim card from specific providers.
I own stocks, all I had to do was fill in the forms on freetaxusa.com based on the forms the brokerage gave me. Just look for non zero fields on the brokerage forms, and fill out the matching box.
If you mean something more sophisticated tax-wise, then I'm sure direct file wouldn't support it either?
Regarding the sim card, I assume that's about two factor codes? IIRC I always logged in through a code received by email.
I'm doing it all by hand because I'm tired of going through the 'free' apps and entering in all my details, and when I get ready to file it end up being hundreds of dollars to file since the other forms (extra 1040 schedules, 2555, etc) are not included.