How to connect disabled iphone 5 to wifi or mobile data ?

If the iPhone is disabled, you need to follow the instructions in If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support

exactly.

That includes the following from that link (begin the following with the phone NOT connected to the computer):

Press and hold the Side (or Top) button until the power off slider appears. Drag the slider to turn off your device. Connect your device to your computer while holding the Home button. Keep holding the Home button until you see the recovery mode screen.

If it is disabled, you cannot connect to the internet. If it won't go into recovery mode the other option is to contact Apple for service. See the following from If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support

If you can't update or restore your device using recovery mode, or you can't use recovery mode because of broken or stuck buttons, contact Apple Support. Then follow the steps to set up service for your iPhone, iPad, or iPod touch.

You can't. You need to connect it to a computer via a cable. See: If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support

Look back at the link that FoxFifth provided. You need to put the device into Recovery Mode if you see it asking for a passcode. That is explained in the link.