What does this command do?

Hello, Im using LCD display with arduino and I have few questions... What does this command do and can i change this numbers in it becasue im only using A5 and A4 pins? LiquidCrystal_I2C lcd(0x27,2,1,0,4,5,6,7);

Thank you.

This is an init of LCD on I2C. Pins A4,A5 (on UNO) have I2C functionality SCL,SDA, so they are required.

I know that they are required, but are those 2,1,0,4,5,6,7 required or I can only write A5 and A4?

Yes you can change it according your needs.

LiquidCrystal_I2C::LiquidCrystal_I2C  ( uint8_t  lcd_Addr,  
 uint8_t  En,  
 uint8_t  Rw,  
 uint8_t  Rs,  
 uint8_t  d4,  
 uint8_t  d5,  
 uint8_t  d6,  
 uint8_t  d7  
)

lcd_Addr[in] I2C address of the IO expansion module. For I2CLCDextraIO, the address can be configured using the on board jumpers. En[in] LCD En (Enable) pin connected to the IO extender module Rw[in] LCD Rw (Read/write) pin connected to the IO extender module Rs[in] LCD Rs (Reset) pin connected to the IO extender module d4[in] LCD data 0 pin map on IO extender module d5[in] LCD data 1 pin map on IO extender module d6[in] LCD data 2 pin map on IO extender module d7[in] LCD data 3 pin map on IO extender module

u dont need to change it. this line is for the init. of the LCD.

i guess you are using a "LCM1602 IIC" LCD ?

Does it use my pins? If it does not, I dont need to change it.

no it doesnt, just ignor it