In short: Yes
KM can generally do that and much more, unless your email app and web site are highly unusual and will not support scripting. When you are ready to proceed, post back here to let us know. We will need to know the details of the workflow you want to automate to best help you.
This forum contains numerous examples of processing email and PDFs. We have tags for both, so you might try these searches to see some examples:
May I suggest that you go ahead and download Keyboard Maestro (free for 30 days), and start becoming acquainted with the many KM features. You will find that this forum is one of the friendliest and most helpful of forums on the Internet. If you have questions (like this one), need specific help, always feel free to post your questions here.
Getting Started with Keyboard Maestro
- Read the Quick Start.
- This is essential to become familiar with KM terminology
- Do the tutorial (Help ➤ Tutorial) in the KM Editor.
- Gives you a live walkthrough of creating a macro in the KM Editor
- Review/Browse the Available Macro Actions
- For Help with an Action in your Macro, click on the gear icon at the top right of the Action, and select "Help"
- Search the Keyboard Maestro Wiki for detailed help.
- Start small, and grow your macros organically.
- Be prepared for some trial and error in the beginning.
- Make good use of this Keyboard Maestro Forum
- Search for existing macros
- Post your questions/issues if you get stuck