PRINTING TEXT :

//header files
#include stdio.h
#include conio.h
void main(){
clrscr();
printf("HELLO ALL WELCOME TO CWS");
getch();
}

PRINTF MEANS PRINT FORMATTING

NEXT INPUT FUNCTION:

//header files
#include stdio.h
#include conio.h
    void main(){
    //variable
    int a;
    //clear output screen
    clrscr();
    printf("ENTER A VALUE:");
    //scanf is a input function
    scanf("%d",&a);
    printf("TYPED VALUE:%d",a);
    getch();
}

NEXT SIMPLE CALCULATOR:

//header files
#include stdio.h
#include conio.h
    void main(){
    //variable
    int a,b,Sum;
    //clear output screen
    clrscr();
    printf("ENTER 1st NUMBER:");
    scanf("%d%d",&a,&b);
    printf("SUM OF NUMBERS: %d",Sum)
    getch();
}

NEXT ELSE-IF FUNCTION:

//header files
#include stdio.h
#include conio.h
    void main(){
    int a,b;
    clrscr();
    printf("enter a and b values:");
    scanf("%d%d",&a,&b);
    if(a>b){
      printf("A IS BIG");
    }
    else{
      printf("B IS BIG");
    }
    getch();
}

FOR MAIN C PROGRAMS: CLICK HERE