To convert scanned images, documents, or anything else for that matter, on a Windows 10 computer, you dont need any paid versions of software. You can do it directly from your computer
Open the folder that contains the documents
Click on the first document
Hold the Shift Key and click on the last document
This will select all of the ones you want
Right click on the highlighted documents
And instead of printing to a Printer, hit the dropdown menu and select Print to PDF
Give the document a name, and you now have a PDF from it!