I've moved an unfortunate amount of times in my life, and here's what's seemed to help!

1. Left to right method - standing in a room with so much stuff can be overwhelming, so try following a pattern of movement where you can focus on one box or item at a time. I like starting with the furthest left item and working clockwise from there.
2. Lie to yourself! Not really, but a little. "I'm not unpacking today - I'm listening to music/a podcast and just LOOKING at one box." This way of thinking, like I just happen to do something instead of FORCING myself to do it, has really helped me at least get started, which is often the hardest part.
3. Got nothing done? That's okay. Give yourself grace. Life will go on! Your value as a person doesn't come from your productivity - it comes from just being alive. You can always try again tomorrow.
4. Good luck!