Do not ship a production app with secrets in the .env file. This tutorial shows you how to upload to IPFS via your react client directly as a demonstration only.
When you are ready for production, you should refactor your application to upload IPFS files using a backend service.
Read this for more context on React environment variables.
This code is for the Tutorial Build your own NFT Marketplace from Scratch built by alchemy.com
To set up the repository and run the marketplace locally, run the below
git clone https://github.com/OMGWINNING/NFT-Marketplace-Tutorial
cd NFT-Marketplace-Tutorial
npm install
npm start