Thank you for contacting Fixya Support, I am glad to assist.
Depending on what type of Internet service you are using, your Intel iMac comes standard with an Airport Extreme wireless card built in. As a result, if you are unable to connect wirelessly to the Internet, you will need to try this:
- Click on the Apple menu icon, located in the upper left corner of your screen and select System Preferences from the drop down menu.
- Now locate Network
from within System Preferences.
- In the side window, make sure you see Airport and check also to see that it is turned on. If it is, then check the left side window to see if the AirPort connection is active.
Keep in mind, your modem or connection router of course, has to be able to provide wireless connectivity, otherwise, if you do not, there will be no need to try connecting via your AirPort Extreme card.
If your network has been physically set as a wireless network, then just turning on the AirPort card in System Preferences>Network will start discovering all networks within its range, including your own network.
So whether you are using an Airport Extreme, Express or a 3rd party (non-Apple-branded) router, you should be able to connect wirelessly.
If you are still unable to connect with these basic steps, here are a few articles you will need to review from Apple Support informational database:Requirements for wireless Internet access with AirPortAirport & Bluetooth interference (for connectivity issues)
So here are some basic steps and resources you can try.
If you have more questions please feel free to post a comment.
I hope this information helps.