To set up Instagram widget please follow next steps.
1. Install Smash Balloon Social Photo Feed plugin.
2. Navigate to WP Dashboard → Instagram Feed → 1. Configure and connect your Instagram account.
3. Open 2. Customize → Layout section and set the layout as following

4. For 2. Customize → Photos → Image Resolution select Medium (320×320)

5. For 2. Customize → Header → Show Feed Header uncheck the option.
6. For 2. Customize → ‘Load More’ Button → Show the ‘Load More’ button uncheck the option.
7. Go to your page, e.g. Home and insert next shortcode using Shortcode widget
[instagram-feed]

No worries if you don’t see your Instagram images in the Elementor. Save your changes and check the frontend page.