where can i get the audio file of HSK stander course?

From their web site. The easiest way is to look at each individual book's page and then click on the "Download" link, which will show you the resources available.

Please note that you need to create and acount and log in in order to be able to download anything. Also, only the items listed as "0 points" are free. You need to get points (buy stuff online) to download the other materials.

https://www.blcup.com/EnSeriesBook/index/8

Book 2 does not seem to have audio files available if you look this way.

Hi,
Here is the audio for the first text audio book:
https://www.ximalaya.com/waiyu/26419256/
When you access this website, it will ask you to download its software. Once you download it, you can create an account (using wechat is the best way). Once you have an account, you will be abble to save your favorite albuns.
In this platform you can find many chinese audio files (like HSK series, Developing Chinese, HSKK books and so on). Here is a screenshot of somebooks I have saved and have been using recently.

On this website if you go to the PDF tab and click on the PDF you will see a button below the preview next to the download button with a note symbol, this is the download for the audio file.