The current Civil 3D sharing plan is opened as a 1-user package, meaning you get your own personal Autodesk account with an active monthly Civil 3D license. You can sign in to your Autodesk Account, download the Civil 3D installer, and activate the software on your device at any time. Since this is a monthly license, the active period follows one calendar month from activation and will be renewed for the next period if you choose to continue.
Because the open plan is a 1-user package, each slot is your personal account, not a shared one. You are free to change your password, sign out other devices, and manage your own Autodesk Account profile without disturbing anyone else. What you must keep intact is the license itself and the account, because disabling the license or deleting the account will make your slot unusable. For group plans with a shared account, JoinBareng will announce separately once that plan is opened.
If you place an order while the group plan is also open, you will wait in the queue until the group is filled according to the maximum quota of two people. While waiting, your funds are not yet charged and you can cancel the order without any fee. Once the group is full, JoinBareng admin will activate the shared Civil 3D account and send the login credentials to your WhatsApp, then you can simply sign in and start using Civil 3D for your infrastructure design work.