Can I access data stored in OneLake from another application?
OneLake is a layer connecting together your data sources. If your data is in a Lakehouse within OneLake (a Lakehouse created will be automatically part of OneLake) - you can access those the same way as an ADLS G2 storage. Right click on one of your tables/files in the Lakehouse and you will get the ADLS path. You can use this in other applications which support Azure ADLS, or in Azure Storage Explorer.