delete multiple documents at once mongodb atlas
You actually can't bulk delete in MongoDB Atlas. See MongoDB Atlas info on the filter section AKA Data Explorer. However you can run standard queries, like find, remove once you connect to the database using your Atlas credentials.
At the clusters view, click connect on the cluster with the collection you would like to query/modify. Then follow the UI to get your connection string using Mongo Shell. If you need a GUI way to delete, you may consider Mongo Compass. Atlas also provides instructions how to connect via Compass on the same page.
I normally use mLab which is owned by MongoDB. There is an option in there for deleteing all documents.
You can use Robomongo which is like Compass but with delete feature so you could use a query like this: deleteMany({name: "dang"})https://robomongo.org/