From Magento Better Blog version 1.0.4 you can:

Modify CMS Homepage

From Admin panel > CMS > Pages > Homepage (your current Default CMS Homepage)

Open Content tab and insert following snippet:

Display 5 recent posts in Magento blog  

{{block type='mageplaza_betterblog/post_recent'  post_count="5" block_name="Latest from the blog" template='mageplaza_betterblog/post/recent.phtml'}}


Display 5 posts in specific category id


 {{block type='mageplaza_betterblog/post_cat'  post_count="5" category_id="4" block_name="Fashion News" template='mageplaza_betterblog/post/recent.phtml'}}


Flush Cache

Now flush Magento cache, navigate your browser to frontend and check result.

Any questions, free to create a topic in Magento forum