Hey Miguel,

1. You can click with the right side of the mouse on your entity and select the option Expose as REST resource.

2. Select all the information needed in the popup

3. Give permission to module roles.

That's it. You can customize your service with more functionalities by checking the links below.

Check this doc: https://docs.mendix.com/howto/integration/publish-rest-service/

Check this video: https://www.youtube.com/watch?v=rMRm5UeWww4

Best Regards,

Ricardo Pereira

Use the documentation