hi,

Try this in xml.view:

<template id="external_layout_footer">
    <div class="footer">
        <div class="text-center" style="border-top: 1px solid black;">        

            <ul class="list-inline">
                <li>Page:</li>
                <li><span class="page"/></li>
                <li>/</li>
                <li><span class="topage"/></li>
            </ul>
        </div>
    </div>     

</template>

for any further information click this link:

https://www.odoo.com/forum/help-1/question/how-to-add-page-number-in-qweb-reports-in-odoo-74996#answer-75267