Your linked images or files will automatically be embedded when you create your PDF document if you choose the [Press Quality] Adobe PDF Preset.
There are two ways to embed links in illustrator
1. From the Links panel, highlight the item(s) and choose Embed Image(s)from the dropdown menu.
2. Or, save the file as an Adobe Illustrator (.ai) format,
3. and then choose the option to Include Linked Files from the save dialog window.
Your linked images or files will automatically be embedded when you create your PDF document if you choose the [Press Quality] Adobe PDF Preset.