It looks like there is lot of inaccurate information on connecting Reliance Wired Broadband connection for Wifi. It is possible to do this and here is a quick guide on doing it using an ADSL modem+router (BSNL's DNA-A211-I is illustrated, you will need to adapt if your router is a different make). This should help you to connect multiple wired and wifi devices at the same time via the router. Note that if you want to use a wired modem + a broadband router, this procedure does not hold good. The assumption is that your broadband input comes in a cable similar to a telephone cable.
Step 1: Physical Connections
Remove the non-wifi router Reliance supplies. Replace it with an ADSL router+modem such as BSNL's DNA-A211-I. The cable coming from the Reliance splitter should go into the slot named 'DSL' and a LAN cable should be connected from any of the 'Ethernet' slots on one end and to the PC's LAN slot on the other end.
Step 2: Computer LAN settings
Right click on the network properties icon in system tray (in windows) - it should normally read Local Area Connection.
Click Properties - Internet Protocol and set up the values similar to this. Click ok and repair connection by right clicking on the system tray icon and choosing 'Repair' to be on the safe side.