Licenses will determine some functionality for users. There are two main licenses. Team Member and Essentials (or Premium but that only applies to manufacturing and service features).
Team Members can't post transactions or create most transactions. They can view data throughout the system. They can also engage in approvals.
Essentials users can complete all functions in the system without restrictions.
If you're coming from Dynamics SL you should be able to simplify and replicate most processes within Business Central. It will depend on how the implementation was done. Business Central can be a bit confusing and frustrating if you come from a simpler system because it has so many modules and there is a lot of visual noise if it isn't configured correctly. It's usually recommended during an implementation (at least the ones i've been involved with) to strip out as much as possible to streamline the user experience. This would involve updating user permissions but would also involve a Profile/Roles cleanup to hide fields you don't need and only display relevant information.
For example here is a simplified general journal page - it just has a few fields and a few options making it easier for users. You can make these changes across all modules in the system:
Teagen
Catapult ERP
