KeePass is a password manager for local usage. With KeePass you create a local database storage file which can be opened via the KeePass application. It is recommended to use a local database for your own personal passwords you might need as well as for any passwords that are shared with you, in case the online password manager is not available.
Under Windows with Scoop, simply install KeePass via
$ scoop install keepass
Under MacOS we recommend KeePassXC.
Create a KeePass database, choose a secure password for it and put the KeePass file (.kdbx) in your ownCloud.