I have an old router that I was wondering if it would be possible to use it as a bridge as such to extend Ethernet For example Main router - Ethernet - Router 2 - Ethernet - device!
Any help would be greatly appreciated
If both routers are functioning correctly, you should definitely be able to do that. Here are some options you can try
Setup 1 -- Internet Service provider -- (WAN)Router1(LAN)--- (WAN)Router2(LAN)--- Assuming both are cable. In this case, keep in mind you might end up having 2 subnets, that of each router.
Setup 2 -- Internet Service provider -- (WAN) Route1 (LAN) --- (LAN)Router2(LAN)--- In this case, you will "lose" one port of the router2 but depending on how old the router is, it should have 'auto sensing' capability that will let your devices connected to Router2 be on the same subnet as that of router1. If you have a DSL router, this might be your only choice.
If your router supports DD-WRT, you could connect a cable to the WAN port of router 2 and still get it to behave like a LAN port/switch.