Can I do the 'Brazlian Blowout' treatment for my hair while I am on Accutane?

It would be reasonable to do a Brazilian Blowout while on Accutance. I would only consider that your scalp might be slightly more sensitive under these conditions.

Yes, you can do any hair treatment you want (dyeing, coloring, cutting, blowouts, etc.) while taking Accutane. "This answer has been solicited without seeing this patient and cannot
be held as true medical advice, but only opinion. Seek in-person
treatment with a trained medical professional for appropriate care."