How to access specific tempate?

how can i access specific template ?

    template:
           home.php
          default.php
          projects:
              default.php
              project.php

how can i access this default.php in project folder?

Your template folder is flat. There is no hierarchy between templates. You can limit which templates subpages can use though.

In your projects blueprint, you can set pages: project to only allow subpages to have the project blueprint, and hence template.

I recommend that you download and play around with the starterkit that offers exactly the kind of architecture you’re looking for. https://getkirby.com/downloads

i have already downloaded that architecture. but i want to use template’s page that is located in folder

I’m sorry, I’m having a hard time understanding your questions. I hope someone can understand and help you out.

The possible templates for a subpage of a specific page are defined in the blueprint for that specific page.

Let’s suppose you have a blog.yml blueprint for your blog overview page and all of that pages children should only just use a blueprint/template called article.yml, you would define that in your blueprint like this:

blog.yml

pages:
  template:
    article

Note that you don’t use the filename extension here!