Drupal - How to get each field value in views-views-unformatted--view-machine-name.html.twig?

As you can see in views-view-unformatted.html.twig, it says what also the commented code you've shown says, there is no fields variable. Therefore, this template is not used for fields.

Available variables:

• title: The title of this group of rows. May be empty.
• rows: A list of the view's row items.
  • attributes: The row's HTML attributes.
  • content: The row's content.
• view: The view object.
• default_row_class: A flag indicating whether default classes should be used on rows.

If you want to use fields in a view template, use views-view-fields--[view-name]--[machine-name].html.twig. There, you can print your fields like this:

<span>{{ fields.title.content }},</span><span>{{ fields.body.content }}</span>

I have found a Way using Kint, You can get field values in views-view--unformatted.html.twig

if you want a specific field

To get text fields value

{{row.content['#row']._entity.field machine name[0].value}}

To get image fields src

{{file_url(row.content['#row']._entity.field machine name.entity.uri.value)}}

To get image alt,title,width,height

{{row.content['#row']._entity.field machine name[0].alt/title/width/height}}

Note : replace field machine name with your fields machine name

If you Want to loop through multiple field

{% for i in range(0, 10) %}
  {{ row.content['#row']._entity.body[i].value }}
{% endfor %}

If you Want raw value

{% for i in range(0, 10) %}
  {{ row.content['#row']._entity.body[i].value|raw }}
{% endfor %}

I have figured a way using kint.

Inside your views-view-unformatted.html.twig use the following code to display your individual fields:

{% for row in rows %}

{{ row.content['#view'].style_plugin.render_tokens[ loop.index0 ]['{{ YOUR_FIELD_NAME }}'] }}

{% endfor %}