Create two file

.env.development

.env.production

In the .env.development keep your env variable of development

In the .env.production keep your env variable of production

To set the env variable

For Windows Command Prompt (cmd):

 set NODE_ENV=development

For Windows PowerShell:

$env:NODE_ENV = "development"

For Unix-like shells (bash, zsh): (Unix-like systems include Linux, macOS)

export NODE_ENV=development