whatsapp_web/views/res_config_settings_views.xml

<odoo>
    <record id="view_res_config_settings_form_inherit_whatsapp" model="ir.ui.view">
        <field name="name">res.config.settings.whatsapp.marketing.form</field>
        <field name="model">res.config.settings</field>
        <field name="inherit_id" ref="base.res_config_settings_view_form"/>
        <field name="arch" type="xml">
            <xpath expr="//form" position="inside">
                <div class="mt16">
                    <h2>WhatsApp Marketing</h2>
                    <div class="row">
                        <div class="col-12 col-lg-6">
                            <field name="module_whatsapp_web"/>
                        </div>
                        <div class="col-12 col-lg-6">
                            <field name="whatsapp_endpoint"/>
                        </div>
                    </div>
                </div>
            </xpath>
        </field>
    </record>
</odoo>