Multiple devices to custom AIO build help

LaatSahab

Herald
Hi all!
I'm looking for suggestions and help in replacing the following devices with a single-box solution:
  1. RPi 4 4GB variant running Deluge, Pi-Hole, Plex Server, and Samba network share
  2. Seagate dock running a 2.5-inch 1TB HDD sourced from an old laptop as Network Storage
  3. TP-Link 5-port desktop switch
Besides these, if it is possible, then I would also like to replace my Airtel modem and have the optical cable go directly to the replacement device.

Discounting the power consideration, for the sake of argument presented here, what kind of device should I be looking for, and what components would it require?