If you're in the Administrators group, then you have the required access for managing network sources. To write policies specifically for network sources, use the network-sources resource type, found with the other IAM components, in IAM Policies Overview.
Apply tags to resources to help organize them according to your business needs. You can apply tags when you create a resource, and you can update a resource later to add, revise, or remove tags. For general information about applying tags, see Resource Tags.