1. Click on Online Store in Shopify and click on customize button.
2. Now select the page from the topbar in which you want to show the Instagram Feed.
3. Now in the left sidebar click on Add Section.
4. Now under the Apps Section Click on Instabox.
5. Now that section will be added.
6. You can also Drag and drop that section to change the position of your Instagram Feed.
Note - You don't need to add any snippet or code manually.