Installing and importing Cisco IOS in GNS3
Open GNS3 and click the Edit file menu and from the sub-menu click Preferences.
Navigate to Dynamips -- IOS routers option in the left pane and click New button in the right pane.
Select the New Image option and click the Browse button. ...
Verify that the correct file is selected and click Next button.
link :
http://tfr.org/cisco-ios/?fbclid=IwAR...