HTML templates or React for Django front end?
Django templates are quite fully featured, and performant, and I'd use them if I could meet the requirements in my project with them alone. Adding react will increase the tooling you'll need and have to maintain, so my team only introduced it after we started to need user interfaces that were react-like (it started when we implemented an in-app to do list). So your project requirements will really dictate if you want to invest additional development and devops energy into react in order to have a more instant-update/native-app-like feel, or not. 
If you are unsure, I'd recommend starting with templates and introducing react later. It's entirely possible to run an app that uses templates for 90% of your app and react only where it's needed (we do this).
I’m creating a big project with Django and wondering if it is sensible to use the HTML template structure for my front end or should I implement something like React? What are each of its benefits? Is it perfectly reasonable to use HTML templates for a big project? Any advice?