Hi venusmakeup
Well, there are two ways to edit 'automatically' the stock.
You can do it from Stock Central. Note that all the values in blue can be edited from stock central. So just edit the stock of the products to the quantity you wish, and then save changes.
Another option is to use our premium add-on ATUM Export Pro. With this add-on you will be able to export almost any kind of data of your site, in your case products, import it on a spreadsheet to edit it in bulk, and then import it again to your site. Once imported your products will display the changes.
I leave you here the documentation of the add-on where you will find useful info about how it works: https://forum.stockmanagementlabs.com/t/atum-export-pro-documentation
And the link to the demo site in case you want to try the free trial: https://stockmanagementlabs.com/addons/atum-export-pro/
Best Regards,
Andrea.