If an A/C have Radio failure ( sqk 7600 ) How the ATC will give him instruction or how will he land ?!
This is a question with many answers, depending on the conditions of the flight. Let me limit myself to private recreational aviation (what the FAA calls Part 91) in a single-engined propeller aircraft.
If you are flying Visual Flight Rules (VFR), there are some airspaces you need to stay out of. For instance, US and Canadian Class B and C airspaces require radio communication. You won't be able to land at airports in such airspaces without some other arrangements.
You can give a signal that you are lacking radio communication. Squawking 7600 on your transponder is one way. Flying a triangular pattern, which might be visible to ATC on radar, is another way. I have sometimes used my cell phone to call ATC's phone number.
Control towers in the US and Canada might well have "light guns": bright spotlights which the controller can point at an aircraft, and colour red or green, and shine continuous or blinking light. A continuous green light from tower to an aircraft preparing to land means that aircraft is cleared to land.
If you are flying Instrument Flight Rules (IFR), there are specific procedures to follow if you are unable to communicate with ATC. Frequently they boil down to holding for a few minutes, then continuing on your flight planned route.
Remember that some aircraft have no electrical system, let alone radios. They fly, take off, and land just fine. There are many airfields with no control towers. There is uncontrolled airspace in which to fly. In these cases, pilots maintain safety by seeing and avoiding other aircraft. Pilots fly traffic patterns before landing, and sequence themselves cooperatively. Lots of aviation works just fine without radio communication between pilots and ATC.