So every time I import a .3ds model, it has multiple parts and I can’t group them together. Like my bird model has two eyes that are separate. When I select the body and the eyes and Add Group it does nothing.
When I go to animate, and move the head, the eyes come off, or if I move it. Any idea how to keep the eyes in the same place as the body when moving or animating it?
Grouping has different purposes. For example for selecting or importing from different blend files.
What you are looking for I believe is parenting. Select eyes, shift select body and press Ctrl+P. The eyes will follow the body now.
For more ‘complete’ animation all this should be done with the armature.
Btw, to join the separate objects into one, just select all and press Ctrl+J