To allow a contact to log in to Centreon:
Go to page Configuration > Users > Contacts/Users and click on the contact you want.
On the Centreon Authentication tab, set Reach Centreon Front-end to Yes.
Fill in the Password and Confirm Password fields. You can use the Generate button to generate a random 8-character string.
Users created this way will be able to change their password when they first log in, by clicking on the profile icon in the top right corner of the page and then clicking Edit profile.