I think these docs will help you :
Mendix offers a toolkit to wrap UI components from other libraries into Pluggable Widgets. Pluggable Widgets (and most of the built-in platform widgets) use ReactJS as their underlying technology. Therefore, it’s very straightforward to create new Mendix widgets on top of existing ReactJS components. It’s also possible to use components from other frameworks, but I would (in general) not recommend it. Here’s a learning path you can follow to get started.
Overall, I recommend using and styling the standard out-of-the-box widgets in Mendix to meet your needs as much as possible. From there, add your own pluggable widgets where necessary to complement them and complete your organization’s design language.