To allow an immediate download of a file after a landing page form is submitted, you will put a URL into the "Redirect to Website" field in the Form Actions section of the Landing Page setup. The URL that you place there can be direct to the file and doesn't have to go to another landing page unless you want to (for instance, you might want to provide more context about the download so having a landing page is helpful). If you want to link directly to the file, you can use GrowthZones' Cloud drive, Follow the steps here https://helpdesk.growthzone.com/kb/article/178-create-a-sharing-link-for-documents-in-the-cloud/ to upload your file to the Cloud and create the URL that can be shared. This will provide a URL that you can put in the "Redirect to Website" field that will immediately bring them to the file download.