question regarding creating a custom theme
Is is possible to create a custom theme that uses react for the frontend? If so how?
Yes you can create your own theme with React.
We have fully working PWA module made on Vue, and also in Velocity theme, components of vue are used.
Similarly, that can be done with React as well.
How to create custom theme in Bagisto, refer this:
You can also check PWA on Bagisto Vue