Ground-fault circuit interrupter.
Not if the GFCI breaker is supplying the circuit you are wanting to put the GFCI receptacle into.
Yes you can. Lots of blow dryers have GFCI protection built in.
my gfci trips when my christmas lights r on and it rains is the gfci bad or is this normal of a perfectly working gfci
GFCI Breakers are quite a bit more expensive than a GFCI outlet. More often than not a typical residence will need only a handful of GFCI outlets that combined together will be cheaper than a GFCI breaker. If you need to protect a series of outlets with GFCI protection you can simply connect the rest of the outlets on that same circuit downstream from the first outlet on the line and make that the GFCI. All you have to do is connect all the other outlets to the LOAD side of the GFCI outlet. If a GFCI fault occurs in any of the outlets down stream they will trip that very first GFCI plug you placed and keep you safe.
Your question is a bit vague, but let's try a two part answer. If you have a GFCI breaker in an electric panel you should only have one connection at the breaker, but the breaker will protect all devices on the circuit. If you are talking about a GFCI outlet, they are equipped to extend the GFCI protection to other non-GFCI outlets by using the proper "output" connection on the GFCI.
A GFCI can detect ground faults on the specific circuit it is connected to. If multiple outlets are on the same circuit protected by a single GFCI outlet, the GFCI can protect all of them. However, if the outlets are on different circuits or not downstream from the GFCI, they would need their own GFCI protection.
Most probably the receptacles downstream from the GFCI would not be protected by the GFCI receptacle.
Deoends on code you are governed by. In USA, a GFCI outlet or a circuit controlled by a GFCI circuit breaker would be required.
No, you could use a GFCI circuit breaker instead.
How far do u put a GFCI receptacle from water
Yes, you install a GFCI on a 2 wire circuit.