I want to combine/attach Pdf files to another pdf file

Hi Kameshak88544012,

I assume you are working on Adobe Reader DC desktop application?

You can add a attachment to the existing PDF file by following the steps mentioned below-

Open PDF>Tools>Comment> Click on the Attach Icon at the top menu bar and "Attach File"

You would be able to see the attached file as comment pane at the right hand side and in the file attachment icon at the left side bar.

If you are working on Acrobat DC then you may refer to the help document and check Add and attachment Links and attachments in PDFs, Adobe Acrobat

Hope this works for you.

Regards,

Akanchha