HI Ramesh Naik,
That's awesome! 🚀 You're making really solid progress.
The things you have learned — there is no specific rule that says we must only use one approach. It all depends on your work, your project, and your requirements.
But normally, we use Viewsets to build REST APIs and Mixins when we need only specific behaviors.
We also use custom classes to build our own logic.
So, the knowledge you have is great!
We have shown the implementation of these concepts in the course, and you can explore them even more by making wonderful projects.
Hope this answers your question. If you need any other help, feel free to ask anytime! 🌟