Intercept all network request of Wifi Router

I am new in this topic, at my home my all devices are connected with my Wifi Router, as per my thought if I can intercept all traffic between router and modem then I can analyse all data (like any device which is connected with WIFI, if execute any network request, I can intercept).

I have no idea how can i able to achieve this can anyone suggest me how can I achieve this?

As per my thought, from modem if I will connect LAN cable to my Linux Computer where WireShark is installed and I will buy USB to Ethernet adapter and from that adapter I will connect LAN cable to Router.

so connection is like

Modem ---> LAPTOP (With Wireshark for intercept) ----> Router

Is this possible? Please let me know. Is it possible, With USB to Ethernet adapter?