A default comments form is automatically created for each blog in your account. You can customize which fields are required here or add additional fields in your forms tool.
In your HubSpot account, navigate to Marketing > Lead Capture > Forms.
To find the comments form you'd like to edit, search for comments form in the search bar. Each form is named with the convention [Blog Title] Comments Form.
Click the form name to make edits.
Click the asterisk next to a field to make it required or click the pencil icon to edit the field options. You can add additional fields by going to the Fields tab in the left sidebar pane and searching or browsing, then dragging and dropping a field on to the form.
When you've made the desired edits, click Save form.
Please note: your blog comments form must include a Name, Email, and Comments field.