Before getting started, make sure you know the Program ID for each program that you're inviting users to join. The Program ID can be found under Settings in the Programs tab. Afterward, create a CSV file that contains the users' email and programid. Your file should look something like this when it is ready to to be uploaded (make sure it is saved as a CSV file).
Once you have the CSV file, navigate to the User Management tab in Settings. Click the Invite New User button at the top right-hand corner of the platform and choose Program Admin from the dropdown menu.
Once selected, a window will pop up. Select the option that says Invite multiple users (bulk).
Select the CSV file from your computer that contains the user information. Then click the Review button. Use this search bar to spot check your users and the invites you're about to send. When confident, click Invite and users will receive an email invitation from firstname.lastname@example.org to create their accounts.