I don't think its necessary to learn a large number of openings - but to have 2 or 3 for playing as black and white. And to be prepared for the unexpected...
Opening principles , types , importance

thanks for comment, yes , you are right but i would like to know at least what are the names of famous openings and which for defense and which for white .
My opening repertoire is:-
As white:-
Italian game - I would recommend the Lolli attack against the two knights defence.
Open Sicilian
Main Line against the French.
Fairly obvious moves against the Caro-Kann
As black:-
French defence.
Queens gambit declined (1.d4 e6 2.c4 d5 [this gives the possibility of transposition into the french if 2.e4])

My opening repertoire is:-
As white:-
Italian game - I would recommend the Lolli attack against the two knights defence.
Open Sicilian
Main Line against the French.
Fairly obvious moves against the Caro-Kann
As black:-
French defence.
Queens gambit declined (1.d4 e6 2.c4 d5 [this gives the possibility of transposition into the french if 2.e4])
thnaks for your comment , actualy i'm new in this web site and i do not know in this software how to drow this symboles in its chess board but i shoud do it some time later .

It depends if you're a tactical or positional player
Open games are better for tactics whereas closed games are more for positional players.
thanks , but what the deference between tactical or positional player .

Forget opening variations, just learn the general principles of opening play and work on your tactics, and play as much as you can, preferably at slower time controls than blitz.
good , what are the general principles of opening play ?

Forget opening variations, just learn the general principles of opening play and work on your tactics, and play as much as you can, preferably at slower time controls than blitz.
good , what are the general principles of opening play ?
The two big ones are control of the center and speed of development.
You want to control the 4 center squares because if you own space in that area it's easier to maneuver to either side of the board. You claim space with pawns. You want to place at least 1 pawn in one of the 4 center squares in the opening.
In terms of development, pawns do not count as development. You want to move each knight and bishop off of their original square, to a place where they help influence the center, and as fast as possible (one move each). You can of course move a knight or a bishop twice in the opening, but only do so for a good reason (winning a pieces or keeping from losing a piece). Starting an attack with only a few pieces developed is bad.
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Other opening principals are castling early to a safe side, developing the less valuable pieces first (knight and bishops before rooks and last the queen). The queen will only develop a few squares away from her home square. You want to castle early and often and you want to avoid capturing without a good reason (captures generally draw more enemy pieces out and you lose time).
There are exceptions to all of these of course, but the first two are pretty much universal. These last few must be known to make it past beginner level, but exceptions to them are more common.
Opening principles , types and importance .
chess opening is very needed for easy play and wining , i just know 3 or 4 types of opening , may some one share me this subject and advice some good types of opining.