Help to setup tailscale network

Can i get some help to setup a tailscale network to match the layout in the above attachment thanks

Setup tailscale subnet-router on “Second Router”.
If your blue iris is on network create a subnet router on “second router” with

tailscale up --advertise-routes=

than allow the subnet router in your tailscale admin interface.
than install tailscale on your client.
you will than be able to connect to the subnet over your tailscale connection.