Question

A set of organized beliefs that is often centered around one or more deities is referred to as

Answer 1

 A set of organized beliefs that is often centered around one or more deities is referred to as RELIGION

Answer 2

I think that the word you're looking for is "religion".

Religion is a set of organized beliefs (or moral philosophy), that is often, but not always (see non-theistic religions) centered around deity(/ies).