Hi

It will help You 

Top menu(Drop down)

<record id="menu_parent" model="website.menu"> 
    <field name="name">Parent Menu</field> 
    <field name="parent_id" ref="website.main_menu"/> 
    <field name="sequence" type="int">50</field> 
</record>

Child menu (Drop down content)

<record id="menu_child" model="website.menu">
    <field name="name">Child menu</field>
    <field name="url">/foo</field>
    <field name="parent_id" ref="menu_parent"/>
     <field name="sequence" type="int">10</field>
 </record>

In Python File

from openerp import http, _ 
from openerp.http import request 

class Bar(http.Controller): 
    @http.route('/foo', type='http', website=True, auth="public") 
    def page_certificate_verification(self, **kw):
        return request.render('Your_module.your_template')

In xml

<template id="your_template">
    <t t-call="website.layout"> 
        <div id="wrap">
            <div class="oe_structure"/>
             <div class="container">
                 <!--Your Contents-->
                 <h1>Foo</h1>
`            </div>
         </div>
     </t>
</template>