WordPress Plugin Maker (standalone version) can generate complete plugin code, and you can also develop a WordPress plugin that customizes features very quickly. e.g. image size, custom post type or database, toolbar..

Demo: https://codecanyon.net/item/wordpress-plugin-maker-freelancer-version/13581496

9 Layout Styles 14 Additional Inner Pages Update: Bootstrap 5 version also included Fully Responsive Layout (PC, Tablet and Mobile phone) Based on Twitter Bootstrap 5.x & 4.3.x jQuery-3.3.1 12 Columns Grid System HTML5/CSS3 W3C valid.

Demo: https://themeforest.net/item/etreeks-online-courses-education-landing-page-template/26143013