To Create a LMS user:
First you have to create a Branch / Department. It is a Section you may in a very simple language. If you have already no need to create it.
Next,
Navigate to Library Management >> Manage Users
Additionally, if you have ID of the user you can put into it’s User / Registration ID field or simply you can see the option (Auto Generate) of LMS to generate a unique ID for your users. It is something like a unique identifier for each user.
That’s it.