How can I enable the menubar to see file tree

I'm a noob who read all the files but cannot figure out how to fix it... Sorry for disturbing. Windows plat form. I use obsidian to manage my notes.
This is my config.yaml file:
baseURL: https://amethyst.bencuan.me

bookFlatSection: false

# Book configuration
disablePathToLower: true
enableGitInfo: false

# # Needed for mermaid/katex shortcodes
markup:
  goldmark:
    renderer:
      unsafe: true
  tableOfContents:
    startLevel: 1

# Multi-lingual mode config
# There are different options to translate files
# See https://gohugo.io/content-management/multilingual/#translation-by-filename
# And https://gohugo.io/content-management/multilingual/#translation-by-content-directory

# Sidebar menu additional links
menu:
  before:
    - name: "Sample"
      url: "https://google.com"
      weight: 10
  after:
    - name: "Github"
      url: "https://github.com/64bitpandas/amethyst"
      weight: 10

params:

  name: 10k
  title: 10k's Digital Garden

  # OPTIONAL: custom favicon location
  # favicon: 'location/to/favicon.png'

  # whether to display on-hover link preview cards
  enableLinkPreview: false

  # Enable rendering of LaTeX blocks
  # (surrounded by either single or double dollar signs)
  enableLatex: true

  # whether to render titles for code blocks
  enableCodeBlockTitle: true

  # whether to render copy buttons for code blocks
  enableCodeBlockCopy: true

  # whether to render callouts
  enableCallouts: true

  # Show footer, including backlinks and graph view
  enableFooter: true

  # whether backlinks of pages should show the context in which
  # they were mentioned
  enableContextualBacklinks: true

  # whether to show a section of recent notes on the home page
  enableRecentNotes: true

  # whether to display an 'edit' button next to the last edited field
  # that links to github
  enableGitHubEdit: false

  # whether to render mermaid diagrams
  enableMermaid: true

  # Link to your Github repo
  GitHubLink: https://tenthousand.cn
    # https://github.com/64bitpandas/amethyst

  # Search (WIP)
  search:
    enableSemanticSearch: true
    operandApiKey: "REPLACE-WITH-YOUR-OPERAND-API-KEY"
    operandIndexId: "REPLACE-WITH-YOUR-OPERAND-INDEX-ID"

  # Site description and title
  description:
    Notes, hosted by me

  # Footer links
  links:
    - link_name: Website
      link: https://bencuan.me
    - link_name: Blog
      link: https://blog.bencuan.me

  # (Optional, default true) Controls table of contents visibility on right side of pages.
  # Start and end levels can be controlled with markup.tableOfContents setting.
  # You can also specify this parameter per page in front matter.
  BookToC: true

  # (Optional, default none) Set the path to a logo for the book. If the logo is
  # /static/logo.png then the path would be logo.png
  BookLogo: /logo.png

  # (Optional, default none) Set leaf bundle to render as side menu
  # When not specified file structure and weights will be used
  BookMenuBundle: "/"

  # (Optional, default docs) Specify root page to render child pages as menu.
  # Page is resoled by .GetPage function: https://gohugo.io/functions/getpage/
  # For backward compatibility you can set '*' to render all sections to menu. Acts same as '/'
  BookSection: "/"

  # Set source repository location.
  # Used for 'Last Modified' and 'Edit this page' links.
  BookRepo: https://github.com/64bitpandas/amethyst

  # (Optional, default 'commit') Specifies commit portion of the link to the page's last modified
  # commit hash for 'doc' page type.
  # Requires 'BookRepo' param.
  # Value used to construct a URL consisting of BookRepo/BookCommitPath/<commit-hash>
  # Github uses 'commit', Bitbucket uses 'commits'
  BookCommitPath: commit

  # Enable "Edit this page" links for 'doc' page type.
  # Disabled by default. Uncomment to enable. Requires 'BookRepo' param.
  # Edit path must point to root directory of repo.
  BookEditPath: edit/main/exampleSite

  # Configure the date format used on the pages
  # - In git information
  # - In blog posts
  BookDateFormat: "January 2, 2006"

  # (Optional, default true) Enables comments template on pages
  # By default partals/docs/comments.html includes Disqus template
  # See https://gohugo.io/content-management/comments/#configure-disqus
  # Can be overwritten by same param in page frontmatter
  BookComments: true

  # /!\ This is an experimental feature, might be removed or changed at any time
  # (Optional, experimental, default false) Enables a drop-down menu for translations only if a translation is present.
  BookTranslatedOnly: false

  # Don't change this
  enableSPA: false
  BookSearch: false
  BookServiceWorker: false
  BookPortableLinks: false
added: bookFlatSection: false
64bitpandas / amethyst

How can I enable the menubar to see file tree #6
