Integrating Clarifai in your React project is very easy, we are providing an easy-to-use API and filled our docs with Javascript REST examples (https://docs.clarifai.com/api-guide/api-overview) so you can use this mini-tutorial as a base for all your Clarifai calls in your React project!
So let's say you're interested in our Face Detection model (https://www.clarifai.com/models/ai-face-detection), first thing to is to find the Face Detection model_id, this article covers how to find any model's model_id: https://help.clarifai.com/hc/en-us/articles/1500007677141-Where-to-find-your-Model-IDs-and-Model-Version-IDs
I'm looking for the "Face" model (visual-detector): 
1. I grab the model_id: f76196b43bbd45c99b4f3cd8e8b40a8a
2. I go over to https://docs.clarifai.com/api-guide/predict/images and grab the Javascript REST snippet for image prediction
3. I notice I need some more infos before being able to call the prediction endpoint so I go to the Clarifai portal: https://portal.clarifai.com/login and I grab my user_id, app_id and PAT ()
4. I complete the rest of the code with the information I got, which results in a similar call:
You can insert this snippet anywhere in your React project!