To create your own 404 page layout with Elementor go to your WP Admin – Theme Builder – 404 Page and hit “Add new” button.
- Add your page title
- Hit “Edit with Elementor” button
- Create your own 404 page layout
- When you finish, save the post and go to WP Admin – Theme Builder – Settings – 404
- Assign the created post layout to “Page content“
- Save the changes and check the result.