Hi there
Thanks for reaching out and sorry to hear you're experiencing trouble copying and pasting text and numbers from your PDF into Excel. Is this an issue with a particular PDF file or with all the PDFs? Please try with a different PDF file and check.
When copying text and numbers from a PDF to Excel in Adobe Acrobat, strange characters can appear due to issues with the PDF's encoding or font embedding. If the fonts of PDF don't have Unicode tables and do not use standard encoding for mapping the glyph indices to characters then you get garbage characters during copy/paste.
Also, there is a possibility the fonts used to create the PDF file are not available on your system. You may try using the PDF Fixup Profile "Embed Fonts" in the Preflight tool to embed the font and check if that helps. However, the font does need to be installed on your system.
For more info. please go through the help page (https://adobe.ly/3RPTwUB)