Don't understand how to implement Ionic menus at all

Ionic Framework ionic-v3
#1

I was going through the documentation for how to add a menu to your app and I got really confused. I did step 1, which was adding the menu to app.html :

 <ion-menu persistent="true"  id='menu' side="left" type='reveal' [content]="mycontent">
    some menu content
 </ion-menu> 
 <ion-nav #mycontent [root]="rootPage"></ion-nav>

But here are the things that really confused me :

1)Why does the menu content need to be attached to ion-nav ?
2)Why does the page that opens the menu need to be the root page ?
3)What does setting persistent to true do ?

Essentially, I want my application to have access to the menu by clicking a menu toggle button in the navbar of that page, and I want all my pages to be able to do this. Simple use case, just need help figuring it out. I just know for sure that I shouldn’t have to set up a button in every .html page and a corresponding openMenu() function in the .ts file to be able to use the menu

#2

just generate an example with menu and see how it works:

ionic start myApp sidemenu
#3

The problem with the side-menu template is that it’s a single page app and I’m working on a multiple page app. So now I’m trying to figure how to open the same menu in different pages

#4

you have to add more pages in app.component.ts
then add those pages in app.html too
done

#5

Okay here’s what I did :

I added this to every page which needs to access the menu -

<button ion-button menuToggle>
   <ion-icon name="menu"></ion-icon>
</button>

The problem is I can only see this menu toggle button in one page, and it disappears in the next. According to the docs, it’s only visible when that page is a root page. But doing

    this.navCtrl.setRoot(theOtherPage)

doesn’t allow you to leave the page, not to mention - I still can’t even see the menu toggle button