Sure. First, a couple of pointers.
- A collection can be either on the server or on the client.
- The collection on the server is not the same as the one on the client even if they have the same name. The one on the client is a representation of the one on the server. It contain a subset of the data.
- You can have a server-only collection which you don’t need to exist on the client
- You can have a client-only collection which is essentially private to that client
What constitutes a bridge between the collection on the server and the one on the client is the publish/subscribe mechanism.
- You take data from the collection on the server and publish it to your client.
- Your client subscribes to that publication and puts it in the collection on the client.
Therefore, as you may probably have realized now, you can take any data from the server and publish it so that it can be put into a collection on the client. That data on the server can perfectly originate from an external API for example.
So, given this preamble, here are some very good resources for you to grasp the whole concept with an easy to follow tutorials: