Hi there,
Page Builders are great if you want to create complex designs that have a lot of special features such as animations, sliders and other fancy elements – but that comes at a cost of having to learn another Tool and will impact performance.
Personally i would stick to the Gutenberg Editor, as its the core interface that is well supported by WP, Themes and Plugin developers.
If you need to add some fancy content for your courses, there are several Block plugins that can extend its functionality. We of course recommend our own GenerateBlocks plugin for that:
https://wordpress.org/plugins/generateblocks/