How to connect multiple ip cloud cameras?

Question

Computer networks

There are 4 IP cloud cameras.
The first question is how to properly connect 4 cameras to the router's local network? If through a switch, then what level?
The second question is how to set up recording on a hard disk of a DVR in a local network? The cameras have an rtsp stream output.

Camera model
Aliexpress camera

Answer 1

If through a switch, then what level?

Any Switch

how to set up hard drive recording

Depends on the registrar. See the instructions for your model.