Hi Sarah 

Thanks for posting in the community! It is unfortunately not possible to convert an existing org chart to a flowchart. You will have to re-create your document to move the boxes around manually. 

If you would like to link your shapes to a dataset without the layout restrictions of the org chart shape library I recommend checking out our data linking functionality. For more information please see the Link Spreadsheet Data to Lucidchart Diagrams Help Center article. 

Please let me know if you have any additional questions!