I can't write any chars on LCD

hello. i'm new in arduino. bought this kit. made same things leds, when tried write text lcd display, i'm failed. followed this tutorial , later others. times had blue screen without words or chars. later, re-uploaded code , several random chars appeared on 1st line. i'm doing wrong?
i'm new , doesn't know precise terms, couldn't describe wiring, used components etc, there yo have pictures:



and code:

code: [select]

#include <liquidcrystal_i2c.h>
#include <wire.h>
 
liquidcrystal_i2c lcd(0x27,16,2);
void setup()  {
 lcd.init();
 lcd.backlight();
 lcd.print("hello!");
}
void loop()  {
}
i'll b happy, answers!!

have checked default i/o extender pins in library match pins used on particular board?

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