ah there has an error with [ symbols, use this new code
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.3/jquery.min.js"></script>
<script>
$(document).ready(function() {
$('[data-section-id="654e393b3cb0792dfdc5ca25"] a.grid-item:nth-child(1)').attr('href','https://jlgroup.squarespace.com/technical-services-overview');
$('[data-section-id="654e393b3cb0792dfdc5ca25"] a.grid-item:nth-child(2)').attr('href','https://jlgroup.squarespace.com/professional-services-overview');
});
</script>
