The "Final Version" typically includes the complete set of progression-based interactions and animations intended for that specific storyline or "initiation" sequence.
You can find the download for this and similar "Useful Feature" packs on community-supported platforms like LoversLab (registration may be required) or via the creator's official distribution channels (often linked through Sims community forums). Installation Instructions Sasha's Initiation (Final Version) Download for...
Use a program like 7-Zip or WinRAR to open the downloaded ZIP or RAR file. The "Final Version" typically includes the complete set
In The Sims 4 game options, go to Other and ensure "Enable Custom Content and Mods" and "Script Mods Allowed" are checked. Sasha's Initiation (Final Version) Download for...
Move the .package and .ts4script files into your Documents > Electronic Arts > The Sims 4 > Mods folder.