Hi Prashant,
Please try following:
{ Name: 'Spend', Url: null }
<ul data-bind="foreach: KpiTilesBobMetadata">
<li data-bind="if: Url">
<a data-bind="attr: {href : Url}, text : Name, if: enable"></a>
</li>
</ul>
This <ul><li> will only show when it contains values</li></ul>