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I read everything on the Internet about galvanic cell but I cannot understand a lot of things:
1. Every metal have ONLY delocalized electrons?
2. Electrons are/move ONLY on the surface and many nucleus form a grid inside?
3. I found just one usable info: deep two metal in electrolyte which soluble in it with different speed. Therefore both of electrodes will be negative but not equally.
3.a. Why the cell voltage doesn't increase without any load until the fastest electrode completely dissolve?
3.b. The metal became smaller-and-smaller and the electrons on it need place to moving. What about this?
3.c. If I get two 9V battery and connect the - terminal of the first to a bulb and the + terminal of second to the same bulb the bulb will light? If yes, one of the batteries will have lots of plus electrons. If not, why not?
3.d. If we connect two 9V battery (- to +) the voltage will be 18V but why? From - terminal some electron will move to the other battery + terminal while the amount will be equal and that's all. Or not? (Obviously not.)
 
Finally and actually this is the most important question: what's happening in a galvanic cell step by step started from I put salt in a bowl of pure water, NaCl become Na+ and Cl- due to bipolar H2O, then I deep a copper and a zinc metal plate into this "salted" water...

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OK, I found some swf with Google: The answer for 3.a. and 3.b. and 3.c is the salt bridge which close the circuit inside battery by connect the two half cell. But why need salt bridge? There is lots of Cu++ around anode, why need Zn++ from the other side to ballance lost two e- on anode?

"potential definition": I now lots of definitions but I'm interesting in WHY?

[Borek]

Half of what you ask is physics 101.

1. Every metal have ONLY delocalized electrons?

Google for electronic band structire. This is a staple of solid state physics.

2. Electrons are/move ONLY on the surface and many nucleus form a grid inside?

Yes about a grid, but no about electrons moving only on the surface. See the band model mentioned earlier.

3. I found just one usable info: deep two metal in electrolyte which soluble in it with different speed. Therefore both of electrodes will be negative but not equally.

Good approximation. As they are not equally negative, there is a potential difference between them.

3.a. Why the cell voltage doesn't increase without any load until the fastest electrode completely dissolve?
3.b. The metal became smaller-and-smaller and the electrons on it need place to moving. What about this?

Not sure what you are asking.

3.c. If I get two 9V battery and connect the - terminal of the first to a bulb and the + terminal of second to the same bulb the bulb will light? If yes, one of the batteries will have lots of plus electrons. If not, why not?

Draw the circuit as it is difficult understanding what you mean. Doesn't sound like the circuit is closed.

3.d. If we connect two 9V battery (- to +) the voltage will be 18V but why? From - terminal some electron will move to the other battery + terminal while the amount will be equal and that's all. Or not? (Obviously not.)

See above. Do you know the potential definition?
 

Finally and actually this is the most important question: what's happening in a galvanic cell step by step started from I put salt in a bowl of pure water, NaCl become Na+ and Cl- due to bipolar H2O, then I deep a copper and a zinc metal plate into this "salted" water...

You have already answered this question in point 3.