Hi Evandro
Hope you are doing well. As described, you want to add rows in the PDF spreadsheet.
Adobe Acrobat Reader DC is a freeware application with limited functionality. It is used for viewing, printing, signing, sharing, and annotating PDFs. It can not be used to edit the PDF file. For more information please look at the help page https://helpx.adobe.com/in/reader/faq.html
Moreover, PDF files are not meant to be edited in such a way. You should either edit the original file and then create a new PDF using Adobe Acrobat DC (Paid service), or export the PDF file to another format (like Word), edit it there and then create a new PDF.
You may also look at the similar discussions listed below:
- https://answers.acrobatusers.com/how-do-I-edit-a-table-in-acrobat-pro-q239729.aspx
- https://answers.acrobatusers.com/it-possible-to-add-delete-or-modify-a-row-column-in-a-particular-table-which-is-already-in-a-pdf-document-q201910.aspx
Regards
Amal