which ai (free of charge) can convert the all kinds of input boxes of a pdf file into fillable and clickable?

https://instafill.ai/tools/create-fillable-pdf 

For free AI tools that turn PDF input boxes into fillable fields, try

Instafill.ai, PDFgear, or LightPDF, which use AI to automatically detect and add text, checkbox, and signature fields to static PDFs, letting you download them as interactive forms, though some free tiers might have limits. 

Top Free AI Options:

• Instafill.ai: Uses AI to scan and map form fields (like name, date, signature) onto flat PDFs, creating interactive ones with text, checkboxes, and signature fields automatically.
• PDFgear: Offers a free online tool to add various form fields (text boxes, checkboxes, signatures) and customize them before downloading the fillable PDF.
• LightPDF: Provides free online tools, including AI features, to convert and edit PDFs into fillable formats. 

• 
  

How They Work (General Steps):

1. Upload: You upload your non-fillable (flat) PDF document to the tool's website.
2. AI Analysis: The AI scans the PDF, looking for field labels (like "Name," "Email") and layout patterns (underlines, boxes).
3. Field Insertion: It automatically places interactive fields (text boxes, checkboxes, radio buttons, signature spots) in the right places.
4. Customize & Download: You can review and adjust the fields (size, type, required status) before downloading your new, ready-to-use fillable PDF. 

4. 
   

While many offer robust free tiers, always check their specific limits on pages or features, as advanced AI functions might require payment.