How to create,insert,delete and reverse signly linear linklist in C++?

The program which I am posting here you will not find any where on internet. It is very easy to understand. I have attached some pics. SO that you can learn the algorithm of this program as well.

#include<iostream>
#include<conio.h>
#include<malloc.h>
using namespace std;
void creat(int m);
void display();
void rev();
void insert(int data,int pos);
void del(int data1);
struct node
  {
     int info;
     struct node *link;
  }*start;
int main ()
{

    start =NULL;
    int ch,n,m,data,pos;
    while(1)
    {
            cout<<"1. Create List"<<endl;
            cout<<"2. Display List"<<endl;
            cout<<"3. Insertion"<<endl;
            cout<<"4. Deletion"<<endl;
            cout<<"5. Reverse"<<endl;
            cout<<"6. Exit"<<endl;
            cin>>ch;
            switch(ch)
            {
                      case 1:
                           cout<<"\nenter num of nodes to create:: ";
                           cin>>n;
                           for(int i=0;i<n;i++)
                           {
                                   cout<<"\nenter data::";
                                   cin>>m;
                                   creat(m);
                                   }
                                   break;
                                   case 2:
                                        display();
                                        break;
                                        case 3:
                                                  cout<<"\nenter data";
                                                  cin>>data;
                                                  cout<<"\nenter position";
                                                  cin>>pos;
                                                  insert(data,pos);
                                                  display();
                                                  break;
                                                  case 4:
                                                          int data1;
                                                            cout<<"\nenter data, u want to del node ";
                                                             cin>>data1;
                                                             del(data1);
                                                             display();
                                                             break;
                                        case 5:
                                             cout<<"\nafter reverse\n";
                                             rev();
                                             display();
                                             break;
                                                                     
                                                             case 6:
                                                                  exit(0);
                                                                 
                                                             default:
                                                                     cout<<"invalid choice";
                                                                     }
                                                                     }
    
     return 0;
}
void creat(int m)
  {
    struct node *temp,*q;
    temp=(node*)malloc(sizeof(node));
    temp->info=m;
    temp->link=NULL;
    if(start==NULL)
     {
     start=temp;
     }

    else
     {
     q=start;
     while(q->link!=NULL)
   
        q=q->link;


      q->link=temp;
    }
  }
  void display()
  {
    struct node *q;
    if (start==NULL)
    {cout<<"List Empty";
    }
    q=start;
    while(q!=NULL)
    {
      cout<<q->info<<endl;
      q=q->link;
    }
  }
  void rev()
  {
    struct node *p1,*p2,*p3;
     if(start==NULL)
     {
       return ;
     }
     p1=start;
     p2=p1->link;
     p3=p2->link;
     p1->link=NULL;
     p2->link= p1;
     while(p3!=NULL)
     {
    p1=p2;
    p2=p3;
    p3=p3->link;
    p2->link=p1;
     }
     start=p2;
  }
  void insert(int data,int pos)
  {
     struct node *temp,*q;
    
     q=start;
     for(int i=0;i<pos-1;i++)
      {
    q=q->link;
      if(q==NULL)
      {
                 cout<<"There are less emelents "<<pos;
                 }
                 }
      temp=(node*)malloc(sizeof(struct node));
     temp->info=data;
     temp->link=q->link;
      q->link=temp;
  }
  void del(int data)
{
    struct node *tmp,*q;
    if(start->info==data)
    {
        tmp=start;
        start=start->link;    /*first element deleted*/
        free(tmp);
        return;
    }
    q=start;
    while(q->link->link!=NULL)
    {
        if(q->link->info==data)           /*element deleted in between*/
        {
            tmp=q->link;
            q->link=tmp->link;
            free(tmp);
            cout<<"Deleted "<<data<<endl;
            return;
        }
        q=q->link;
    }
    if(q->link->info==data)
    {
        tmp=q->link;
        free(tmp);
        q->link=NULL;
        return;
    }
    cout<<"Element "<<data<<" not found"<<endl;
}