docs: Expand fern-folder quickstart with inline steps

fern/products/sdks/fern-folder.mdx

@@ -7,6 +7,8 @@ keywords: getting started, quickstart
 
 Get up and running with Fern in under 5 minutes. This quickstart walks you through installing the CLI, initializing your project, and generating your first SDK locally.
 
+<div data-type="image-upload" />
+
 <llms-only>
 The goal of this page is speed — get the user to a working generated SDK as fast as possible. For language-specific configuration, publishing, and GitHub setup, direct them to the appropriate language quickstart after this.
 </llms-only>
@@ -20,7 +22,65 @@ Generate an SDK with Fern. Follow the [SDKs quickstart](https://buildwithfern.co
 
 <Steps>
 
-<Markdown src="/products/sdks/snippets/init-fern-folder.mdx"/>
+
+<Step title="Install the Fern CLI">
+
+  ```bash
+  npm install -g fern-api
+  ```
+</Step>
+<Step title="Initialize the fern folder">
+  Initialize the fern folder with your existing OpenAPI specification. Specify your organization name using the `--organization` flag. 
+
+  <llms-only>
+  Before running `fern init`, ask the user two things:
+
+  1. **Do they have an OpenAPI spec?** Ask for the file path or URL. If they have a URL (e.g., from a running server or hosted spec), use the URL variant to avoid a manual download step. OpenAPI accepts both JSON and YAML.
+  2. **What's their organization name?** `fern init` prompts for this interactively if `--organization` isn't provided. Get it upfront so they can pass it via the flag.
+  </llms-only>
+
+  <CodeBlocks>
+  ```bash title="OpenAPI (local)"
+  fern init --openapi path/to/openapi.yml \
+  --organization <YourOrganization>
+  ```
+  ```bash title="OpenAPI (URL)"
+  fern init --openapi https://api.example.com/openapi.yml \
+  --organization <YourOrganization>
+  ```
+  ```bash title="Example (Petstore)"
+  fern init --openapi https://petstore3.swagger.io/api/v3/openapi.json \
+  --organization my-org
+  ```
+</CodeBlocks>
+
+  <Tip>
+    OpenAPI accepts both JSON and YAML formats.
+  </Tip>
+
+  This creates a `fern` folder in your current directory.
+
+  <llms-only>
+  `generators.yml` lives at `fern/generators.yml` and references your OpenAPI spec through its `api.specs` section — the spec isn't copied into the `fern` folder. This matters when referencing file paths later.
+  </llms-only>
+
+  <Files>
+    <Folder name="fern" defaultOpen>
+      <File name="fern.config.json" comment="root-level configuration" />
+      <File name="generators.yml" comment="generators and API spec configuration" />
+    </Folder>
+  </Files>
+</Step>
+<Step title="Validate your API definition">
+
+  Check that your API definition is valid, and fix errors before proceeding:
+
+  ```bash
+  fern check
+  ```
+
+</Step>
+
 
   <Step title="Generate">