The answer to all your questions is yes:

• you can store pdfs or other files either in Content Builder or in your sFTP
• you can use AMPscript to attach the files to your emails
• you can use AMPscript to dynamically match subscriber data with files and to create conditional statements
• you can match a file based on a filename, customer key, etc.

Some examples can be found in the ampscript.guide: https://ampscript.guide/attachfile/

The answer to all your questions is yes:

• you can store pdfs or other files either in Content Builder or in your sFTP
• you can use AMPscript to attach the files to your emails
• you can use AMPscript to dynamically match subscriber data with files and to create conditional statements
• you can match a file based on a filename, customer key, etc.

Some examples can be found in the ampscript.guide: https://ampscript.guide/attachfile/

Here is one of the examples from ampscript.guide:

This example attaches a Content Builder asset by Customer/External Key:

%%[

var @customerKey, @fileAlias
set @customerKey = "LoyaltyMembersCB"
set @fileAlias = "LoyaltyMembers_ContentBuilder.zip"

AttachFile("ContentBuilder", @customerKey, @fileAlias)

]%%

Make sure to contact SF support to enable attachments in your account first.