Absolutely! It is possible to duplicate an existing app template in Fulcrum. To do this, all you need to do is go to Apps, from the left-hand side menu and click on Apps.
Then click on the More menu (three dots icon) to display the available options, From that list, click on the Duplicate App option. This creates a copy of the app, with all the form fields and configurations, but the data will not be copied.
Notes
If you desire the data to also be copied, you will need to export the data out of your original app and import the data into the newly duplicated app.