The wireless Linksys router is positioned in the living room of the main house which is located about near the center so the signal is pretty good anywhere you're at.
I have a guest house in the backyard but the electronic devices cannot pick up the wifi signal. I have a laptop back here which is about 50 feet away from the wireless router. Will a wifi range extender help in this situation? I want to get good internet connection and speed as I do in the main house but not sure if a wifi range extender can accomplish this.
It will do better than nothing, but that's a long way from the router with lots of potential interference sources in between.
Is running an ethernet cable or coax an option? You can run ethernet or create a MoCA network using coax that you can bury in a conduit like PVC.