You can use Power Automate to save incoming email attachments to OneDrive or SharePoint.
This is the flow we are going to create, in this example it saves to OneDrive.

The settings for When a new email arrives:

In my example I am only going to process emails that have the word “Quote” in the subject.
The Foreach settings are:

The Condition filters to only process pdfs.

Lastly the true condition:

Note when selecting the File content it will appear as Attachments Content.
