Hocalwire

Step 1:- 

Go to preferred CMS - Stories - Create Story - Story Editor

 Step 2:- 

Story Editor: - Where you write your story content, 

Click on the Gallery

 Step 3:- 

Story Editor: - After Clicking on Gallery, you can select images from the library (Which are in your system)

Or 

if you want to upload an image from the system which is not already uploaded in Hocalwire CMS then you can use Pictures Tab