To hide post date on the property card:

Please add this CSS code

.mh-post-grid .mh-caption {
display: none!important;
}

In this article you can find information how to add custom CSS to any WordPress Theme: How to add CSS code that is future update compatible

If you wish also to hide date on the single blog page

Please add also this code:

.mh-post-single__meta> li:first-child {
display: none!important;
}