Users management for GitLab Silver (and higher)

Hello everyone,

I’m looking at GitLab Silver subscription and can’t figure out how users are added to this subscription.
Do all people in company need to create new GitLab’s accounts related to this subscription only, or they should have their personal accounts on gitlab.com that will get access permission to coporate subscription?

Honestly - I wans to check if first option is possible

Thx in advance