Guessing Game Questions

Guessing game that I got from a youtube video and wanted to ask a few questions that I didn't get. One what is the point of the else outofGuesses=1 part? Secondly when do you use one equal sign and when to use 2. Last but not least was there an easier way to do this like using a for statement?

#include <stdio.h>
#include <stdlib.h> 

int main(void) 
{
    int secretNumber= 5;   
    int guess; 
    int guessCount=0; 
    int guessLimit=3;
    int outofGuesses=0; 

    while(guess !=secretNumber && outofGuesses ==0)
    { 
        if(guessCount< guessLimit)
        { 
            printf("Enter a number between 1 and 10:"); 
            scanf("%d", &guess); 
            guessCount++; 
        } 
        else 
        { 
            outofGuesses =1; 
        } 
    } 
    if(outofGuesses==1) 
    { 
        printf("You lost!");
    } 
    else
    { 
        printf("You win!");  
        return 0;   
    } 
}