Annotations can be made to a 3D part through, for example, the Text with Leader tool, within the Part Design workbench Annotations toolbar. Additionally, these can be viewed parallel to the screen by going to their Properties and Display tab, once an annotation has been placed into the model.
Finally, links can be attributed to them through the text box, by Right Clicking the text in it and selecting the option Attribute Link.
The following video details the process:
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