Let's get a look on the Dataverse SDK : CrmServiceClient supported kind of authentication. How and when to use them. Read it!
Session timeout setting with D365 : An article that describes this new setting that could help you to improve security.
Security Roles are so important on Dataverse, Microsoft has recently implemented a new feature to make it even more powerful, to allow you to use different role on different BU level. So great. Please read this article on : Dataverse Modernized security model for Business Unit
Solutions are very important in D365, this article is about Dynamics 365 Solutions explanation and an overview of ALM. After reading it you will be more comfortable with this topic.
Security roles in Microsoft Dynamics 365 are a matrix of privileges and access levels for the various entities. In this article, we will deep dive into the specifics of this essential component of Dynamics 365!