Sometimes, web owners may want to collect images, documents, videos or any files from customers via an online form. It means customers should be able to upload files along with submissions.
Blue Form Builder by Magezon can help do this in minutes by adding a field upload field to a form. Let's see how.
https://www.magezon.com/magento-2-form-builder.html

Step 1: Open the form builder section in the edit page of a form.
Step 2: Click plus icon in the top menu bar and a popup containing all elements will appear.
Step 3: Find File Upload element and click on it to add the element to the builder section.
Step 4: After the element is added, a popup containing its settings will show up. Please pay attention to 2 tabs:
1. Validation tab: customize allowed file types, min/max number of files and min/max file size to upload.
2. Advanced tab: set the field to be required or not, allow uploading multiple files at a time and allow drag & drop interface.

* Please note that you can attach uploaded files to email notifications sent to admins and customers.