“I want to print to a printer in another room from my MacBook. Is there any way I can print wireless from my MacBook or do I need to get a long cable?”
There are a number of factors that will determine the best way for you to print wirelessly from your MacBook, but none of them should result in you needing a long cable. A printer connected to anther computer can typically be connected to using network printing. If the printer is standalone and connected to your network, you should be able to locate it on the network. Or if neither of those options is available, you can setup the printer for wireless printing using a wireless network adapter.
For a printer connected to another computer via USB, you would need to make sure the other computer is on anytime you want to print. Setup printer sharing on the computer with the printer attached to it. On your MacBook you will need to know the IP address of the computer with the printer, which will be used to connect to the printer when you set it up for the first time on your MacBook.
If the printer is a standalone printer connected to your network, you should simply need to know the IP address of the printer. It will be available on the network without any additional connection as long as the printer is turned on.
If neither of the previous two options will work for your specific wireless printing needs, there is a third option. You can connect the printer to a wireless print server. This works by connecting the USB cable from the printer to the print server. The print server connects to your wireless network. You then need to know the IP address of the print server, which allows you to configure it as the network printer on your MacBook. In many cases, this may be your best bet so that you aren’t relying on another computer to be turned on and you also don’t need to worry about which room the printer is located in.