You can script out the objects and make changes, but this is not a rollback. It's a roll forward.
If you are just changing procs/functions/views, just make a dacpac of the existing state and apply that, as noted above.
However, if you have table changes, this is dangerous. It's not simple and a db restore might be needed. It's just hard to tell what you need to do with a simple "rollback a dacpac" question