When adding satellites can a router act as a satellite?

Probably not, bit it depends on what you mean by satellite and what router you are talking about. They aren't all the same.

 

In general just about every router can work is a wireless access point.

 

To see what your router can handle, manuals are always a good place to start.

Visit the support pages:

Support | NETGEAR

Feed in your model number and check the documentation for your hardware.

Look for the model number on the label on the device.

The manual will tell you what you can do with the device.