doc(prisma-config): update example using environment variables (#7203)

Author: mhartington

content/200-orm/500-reference/325-prisma-config-reference.mdx

@@ -356,7 +356,28 @@ export default {} satisfies PrismaConfig;
 
 ### Using environment variables
 
-When using `prisma.config.ts`, environment variables from `.env` files are not automatically loaded. You'll need to:
+When using `prisma.config.ts`, environment variables from `.env` files are not automatically loaded. If you're using node or deno, you'll need to: 
+
+1. Pass a `--env-file` flag to the command line 
+
+<TabbedContent code>
+<TabItem value="Node">
+```terminal
+node --env-file=.env index.js
+node --env-file=.env --env-file=.local.env index.js
+```
+</TabItem>
+<TabItem value="Deno">
+```terminal
+deno run --env-file main.ts
+deno run --env-file=.env --env-file=.local.env main.ts
+```
+</TabItem>
+</TabbedContent>
+
+For Bun, `.env` files are automatically loaded.
+
+For releases of Node before v20, you'll need to: 
 
 1. Install the `dotenv` package: