if Statement :

The if statement is a selection control structure that allows a program to
execute a statement or block of statements only when a specified condition is
true. If the condition evaluates to false, the statement following the if
keyword is not executed.

The if statement is commonly used to implement simple decision-making logic in
programs.

SYNTAX:

if (condition)
    statement;

EXAMPLE:

#include<stdio.h>
int a=300;
int main(){
    if(a>=100){
        printf("a is greater than or equal to 100",a);
    }
   return 0; 
}

Output:

a is greater than or equal to 100