Looking for material to learn about access control

I have worked in IT for many years, and door access has now been given to me. I have been in touch with five vendors that serve our area and each has promised to come and resolve issues we have/features we would like to integrate, but none have fulfilled that promise.

Does anyone have any suggestions on how to learn about access control? (Out system is a Kantech system integrated with Entrapass Corporate Edition v 8.62.192)