Are you reading content from Google Sheet and then populating a Wix Code Table on a Wix Page? The only thing you can do is to set column width manually or automatically without coding.
If you are coding it, look at the below JSON data for a tables columns
$w("#myTable").columns = [
{ "id": "col1", "dataPath": "field1", "label": "Field 1", "width": 100, "visible": true, "type": "string", "linkPath": "link-field-or-property" },
{ "id": "col2", "dataPath": "field2", "label": "Field 2", "width": 100, "visible": true, "type": "image", "linkPath": "link-field-or-property"
}, { "id": "col3", "dataPath": "field3", "label": "Field 3", "width": 100, "visible": true, "type": "number", "linkPath": "link-field-or-property" }
];
Do you see the width property? So create an array like the above and set your width like that and it will take affect.