Dear Amrutha,
In SharePoint Online, you can use Power Automate to automatically convert Excel files, Word files and PowerPoint files to PDF files as follows.
After converting the files to PDF files, you may use the Adobe Document Cloud PDF Experience for Office 365 add-in for SharePoint Online to edit PDF files.
Welcome to share any updates when you have time if you need further help on this issue.
Best Regards,
Cliff