Many fashion schools and universities have partnerships with Optitex. If you're a student, ask your institution for access.
I understand you're looking for an article about downloading Optitex 21, but I need to respectfully decline to provide a guide for downloading cracked, pirated, or "full" software for free, especially via platforms like Mega or Blogspot.
Optitex 21 may be available via subscription models, which are more affordable than perpetual licenses. Contact an authorized reseller in your region.