The 877W runs what is called Cisco IOS. The 877 is part of their ISR line up of routers. The syntax of how IOS works is pretty much the same across all of Cisco's products which run IOS. It's a good router to get started in the world of Cisco. But it's a steep curve. My suggestion is if you want to learn IOS is to go out and buy the two volume CCNA exam prep books. The setup for the routers do have a web interface which I think is called SDM. I've never used the SDM. And most people who configure Cisco routers never use any GUI type interfaces....just command line. To access the web interface you have to know what the IP address(es) configured on the router. Short of that, you can use the console port. This is a serial interface which you'll need a DB9 to RJ45 cable to connect to. If none of your PCs have a 9 pin serial interface, you'll have to get a USB to serial converter. You'll also need some sort of terminal software to access the Com port of your PC which you have the console cable connected to (serial or USB to serial). In the old days, many people used HyperTerminal but most use Putty today.
The last hurdle you'll have to get into the router from the command line is to enter login credentials. You might have to enter user login and password and then an enable password, or just an enable password, or just a user login and password. It really depends on what the configuration of the router is currently. But you need to get to what is called privileged mode which is what the enable password is. You can tell which mode you're in by looking at the prompt. If it is a > then you're just in a very basic access mode. If the prompt is # then you're in the privileged mode.
I don't know if the 877W has extender capabilities. Of all the Cisco devices I've been able to lay hands on, I never touched any of their wireless equipment.
The last hurdle you'll have to get into the router from the command line is to enter login credentials. You might have to enter user login and password and then an enable password, or just an enable password, or just a user login and password. It really depends on what the configuration of the router is currently. But you need to get to what is called privileged mode which is what the enable password is. You can tell which mode you're in by looking at the prompt. If it is a > then you're just in a very basic access mode. If the prompt is # then you're in the privileged mode.
I don't know if the 877W has extender capabilities. Of all the Cisco devices I've been able to lay hands on, I never touched any of their wireless equipment.