My Toyota indus 97 is vibrating when radiator fan and lights are on. This also cause power steering problem, which gets hard with vibration.

It vibrates ONLY when the fan is on? Take a look at the fan itself, may have a bad bearing or even a blade out of whack. But I don't see why that would affect power steering. Take a look at your serpentine belt too, one of the pulleys or tensioners or idler pulley may be going bad. Typically you can put a socket on the tensioner to release the tension on the belt, then take it off. Spin each pulley by hand, especially the ALTERNATOR DECOUPLER PULLEY, look/listen/feel if one is bad. (if the ADP went bad it might be vibrating when under load).