Newbie just tsrating, need help with a sketch

Projects Programming
47

So I've gone back a step or two to try and learn :slight_smile: , and see if I can turn on an LED after 5 seconds, i thought this woudl work but it's not, where have i gone wrong

int ledPin = 12;        
unsigned long previousMillis;
unsigned long currentMillis = millis();
boolean doBlink;

void setup() 
{
   pinMode(ledPin, OUTPUT);      // sets the digital pin as output
}

void loop () 
{
  unsigned long currentMillis = millis();
  if( currentMillis - previousMillis >= 500)  
  { doBlink == true;
  
  }

  if (doBlink) {

    digitalWrite( ledPin, HIGH); 
   
  }
    
  }