If you found this link on a site like Mega.nz or MediaFire , check the original post (often on a forum or a Twitter/X fan account) for the decryption key.
If you have the file but need a password or a way to open it: Download Suisei20210714 rar
These specific archives usually circulate in dedicated fan Discord servers (like the Hololive Fan Server ) or on subreddits like r/Hololive . If you found this link on a site like Mega