it is likely that the camera is set to focus priority for release, put the camera into fully manual mode by selecting M on the mode dial then put the camera into manual focus mode, by the select switch on the side of the lens, try to manually focus on something using the viewfinder, can you focus manually and does the shutter fire. if so you are dealing with an autofocus problem. given that this camera does not have a built in autofocus motor the problem lies with the lens and not the camera body, the kit lenses are relatively cheap to replace so you may as well give a bash at repairing the autofocus motor yourself. I cant really recommend a guide on how to do this as I don't know which lens you have.