Hi Zian,
Thank you for your question.
In terms of security, we strongly recommend always setting referrers among other things you can read here. To learn how to create API keys programmatically, you can refer to this Postman collection you can use the createApiKey function implemented in ArcGIS REST JS.
About monitoring usage you are right, from an organizational point of view there is no dashboard to monitor the use of all API keys. If I am not wrong it is something that is being worked on, just in case I have checked ArcGIS Ideas, but I haven't seen that idea being shared.
I recommend you to request that feature in this forum, if you do, please explain to us what functionality/filters/etc you would like to find there. This is the best way to share your requests with the product teams. If you have an example of the ideal dashboard you would like to see, please feel free to share it with other colleagues. The most upvotes it receives, the better.