Are you referring to a regular paddle fan or an exhaust fan? In simple terms, if there isn't already a pull chain there you cannot add one (unless there are provisions for one and it has just broken off). You're better off using a switch to control the fan.
You don't.
This sounds very strange. You should not have an unswitched bathroom light. Replace fixture with one with a pull chain. Turn breaker off before changing the fixture.
Open up the ceiling box and disconnect the blue wire coming from the light and connect it to the black wire coming from the fan. Be sure and put a wire nut on the wire where the light was connected before you removed it. The wall switch is controlling power to the wire where the fan is connected so when you connect the blue fan wire to that connection you will be sending power to both the fan and light from the wall switch.
If it is a ceiling fan, then there is a little chain on the base of the fan, not the light chain...usually on the opposite side, that you need to pull and it will change direction.
Assuming the ceiling fan also has lights then that is what the second lead is for. You can tie the black & blue together and attach them to black lead in the lighting box. The light and fan will come on together when you flip the light switch and you have to use the pull chain on it for control. ALWAYS connect the green ground wire to the house wiring ground. This is a SERIOUS safety and fire hazard issue if you do not.
decomposer
yes
no, no it cannot
Usually not. Some car engines use a chain for the valve timing, but it's quite different from a bicycle chain. Cars that have electrically opened doors may have a chain quite similar to a bike chain in that mechanism.
they both connect
The purpose of a chandelier chain is to support a chandelier. A chandelier is a type of light that hangs from the ceiling. It is usually quite large and heavy so a strong chain would be required.
A dirty or old ceiling fan pull chain switch.
If you are referring to a porcelain or plastic ceiling light fixture most do not have a place to connect the ground wire. You cannot ground these type fixtures. Just connect the ground wire to the mounting crossbar and forget about connecting it to the light itself. It is on the ceiling and will never be touched unless you change the bulb and then you will have the switch in the off position. It is perfectly safe.
This sounds very strange. You should not have an unswitched bathroom light. Replace fixture with one with a pull chain. Turn breaker off before changing the fixture.
it is like story but the problem is connect to solution
Just remove the old light and install the new pull chain light connecting the black wire to the copper screw and the white wire to the silver screw. There is no connection for the ground wire. Just shove it back into the ceiling box.
A "pee chain" is a line of people waiting to use the bathroom. It is often seen at events or busy public restrooms where there are limited facilities available.
Open up the ceiling box and disconnect the blue wire coming from the light and connect it to the black wire coming from the fan. Be sure and put a wire nut on the wire where the light was connected before you removed it. The wall switch is controlling power to the wire where the fan is connected so when you connect the blue fan wire to that connection you will be sending power to both the fan and light from the wall switch.