Once you are editing a page in Visual Composer mode it is unwise to switch to the Classic Editor. If you do switch and make changes to the page then you are likely going to break the Visual Composer shortcodes and then the entire page will turn into a useless mess of code.
To show you how Visual Composer mode looks like, please follow the steps below
Step 1 Login to WordPress control panel
Step 2 In this tutorial, we will create a new page. Go to Pages > Add New
Step 3 Click BACKEND EDITOR to switch to Visual Composer mode.
Step 4 You should now see the Visual Composer mode
To view the classic editor mode, please follow the steps below
Step 1 From the Visual Composer mode, click on CLASSIC MODE
Step 2 You should now see the classic mode.