Why is my three column block code not working as expected?

this is the code i have written but when i was adding this its not doing what I exactly want to do
Design Image is attached

{{section.settings.subheading}}

{{section.settings.heading}}

{% for block in section.blocks %} {% case block.type %} {% when 'block' %}
{% render 'icon', icon: block.settings.icon, size: 'small' %}
{{block.settings.text}}
{% when 'image' %} img {% endcase %}

{% endfor %}

{% schema %} { "name": "Benefits", "settings": [ { "type":"text", "id":"subheading", "label":"Sub Heading", "default": "The Benefits" }, { "type":"text", "id":"heading", "label":"Heading", "default": "Vapor Cup" } ], "blocks":[ { "name":"Block", "type":"block", "limit": 6, "settings":[ { "type": "select", "id": "icon", "label": "Icon", "default": "", "options": [ { "value": "", "label": "No icon" }, { "value": "smile", "label": "Smile" }, { "value": "wallet", "label": "Wallet" }, { "value": "smoking", "label": "Smoking" }, { "value": "skull", "label": "Skull" }, { "value": "users", "label": "Users" }, { "value": "user", "label": "User" }, { "value":"holding heart", "label":"Holding Heart" } ] }, { "type":"text", "id":"text", "label":"Type Your Text", "default": "Default Text" },{ "type": "select", "id": "icon2", "label": "Icon", "default": "", "options": [ { "value": "", "label": "No icon" }, { "value": "smile", "label": "Smile" }, { "value": "wallet", "label": "Wallet" }, { "value": "smoking", "label": "Smoking" }, { "value": "skull", "label": "Skull" }, { "value": "users", "label": "Users" }, { "value": "user", "label": "User" }, { "value":"holding heart", "label":"Holding Heart" } ] }, { "type":"text", "id":"text2", "label":"Type Your Text", "default": "Default Text" } ] }, { "name":"Image Block", "limit":1, "type":"image", "settings": [ { "type":"image_picker", "id":"centerimg", "label":"Upload Image" } ] } ], "presets": [ { "name":"Benefits" } ] } {% endschema %}