To add many users to your community and import all their data at the same time, see our article Bulk Import with the User Records Template.
If you're looking to add just one or a few users to your 360Alumni community you can either:
Here's a little known tip: Gmail / Google Workspace lets you add "+anything" to the first part of your email address and it will be delivered. For example, when setting up an account for Jane Doe, a new user in your community, and your email address is d.smith@college.edu, you can try d.smith+janedoe@college.edu and you will receive the confirmation email.