Hi @CrystallSalmon,
Editing is generally controlled at the layer level. Sharing an editable layer publicly will allow anyone to edit it. Since you only want people in the organization to edit the layer, sharing it publicly is not advised.
One best practice for the workflow you brought up is to have 2 versions of the layer: one that is editable by the organization and one that is viewable by the public. You can achieve this using Hosted Feature Layer Views.
For example, you could have:
- an editable hosted feature service, shared at the organization level, in one app and
- a non-editable view of that service, shared with the public, in another app
See this article for more on creating hosted feature layer views: https://doc.arcgis.com/en/arcgis-online/manage-data/create-hosted-views.htm
