add image to markdown file code example

Example 1: how to insert an image in markdown

![image info](./pictures/image.png)

Example 2: add image in markdown

![alternative text](image_name.png "Image Title")

Example 3: markdown image

![GitHub Logo](/images/logo.png)
Format: ![Alt Text](url)

Example 4: markdown image

![GitHub Logo](/images/logo.png)
Format: ![Alt Text](url)