Vaultwarden is one vault for your team's logins, shared only with the people who need them. Your staff use it through the Bitwarden apps and browser extensions. Vaultwarden comes from its own open-source project, not from Bitwarden.
It comes with the Office solution.
What Clusterz sets up
Vaultwarden and its database, at its own web address, with an admin page. Anyone signing up needs an invitation. It is sized for about 100 people.
To add it on its own, open Vaultwarden on its own. Install a set or an app gives the steps.
How to sign in
How to sign in opens Vaultwarden's admin page, where the password is the admin token. Invite your people from there. Each person then signs in at the app's address. First sign-in to an app says how to reveal the token.
Licence
Vaultwarden is open-source, under the GNU Affero General Public License 3.0, which applies to your use of it.
Learn to use it
Training your staff stays with you. Vaultwarden's project keeps the Vaultwarden wiki, and Bitwarden's help centre covers its apps.