Student or Learner
I'm interested in the way of linking words in spoken English. Recently, I've seen a movie and I noticed in the one scene that actors linked the words in the phrase "but you still got a lot of packing to do" like this: [packinudu]
so does it always go like this "ing+to"=[inu]?
I say "packing t'du" (in your notation). It's unlikely I'd understand "packinudu" especially in a Russian accent.
If you start slurring words together because you saw it in a movie, generally you won't be understood. Most learners should not try to emulate such shortcuts until their English is good enough that certain elisions, etc. become natural because that's how their friends and colleagues talk. But this is an unconscious process.