If you click on the hamburger menu you will have the choice of New folder, Library setting, and new document library.

See here how the 'upload a zip / file structure' function works.

See here how the access overview works

See a history of your previous zip uploads

To upload a new revision of a document click the new revision button. This will open the file explorer and there you can choose the file you want to upload.

If you have document statuses enabled in document settings you will be able to upload a new draft of a document by clicking the new draft button. This will open the file explorer and there you can choose the file you want to upload.

If you have full access to the document/folder you will be able to move folder(s) or document(s). When you press the move button you will get a window that asks you where you want to move the document(s) or folder(s) to.

If you have full access to the document/folder you will be able to delete folder(s) or document(s). When you press the delete button you will get a window that asks you if you are sure.