docs: add usage section with detailed info about project addition

README.md

@@ -54,6 +54,22 @@ To seed the database with initial data, use the following command:
 npm run db:seed
 ```
 
+## Usage
+
+### Projects
+
+To add a new project, use the following command:
+
+```bash
+node index.js project add [--name <name>] [--github-urls <urls...>] [--category <category>]
+```
+
+For example, to add a project named "express" with GitHub URLs:
+
+```bash
+node index.js project add --name express --github-urls https://github.com/expressjs https://github.com/pillarjs https://github.com/jshttp --category impact
+```
+
 ## Debug mode
 
 This project uses the [debug library](https://www.npmjs.com/package/debug), so you can always use the environmental variable `DEBUG=*` to print more detailed information of the execution.