What do you expect?
Do you want to have your local database in your cloud application as well? In that case you can make a back-up of your local postgress database and restore this on for example a test environment. See https://docs.mendix.com/developerportal/howto/how-to-restore-a-backup
Your database when running locally is separate from when you deploy to the cloud.
You can download the backup from your cloud environment and use it when running locally, but I still don’t think it’s possible to restore your local database to the cloud environment. The local database and cloud database are two different types. I would maintain your data in the cloud and use the back up locally.
Here is a good tutorial on setting up using the cloud back up locally.