If they are using Whova (or some other app) for the conference, I strongly recommend using it and connecting through there in addition to the rest. It makes it easier to coordinate meetups and you can contact authors through it.

Go to the poster sessions and talk to people, it's a lot better way to make real connections than talks (though in the years just before covid, they were starting to get a bit over-crowded). If you see someone alone, approach them. A lot of this comes down to "don't be shy". You will get a lot more from NeurIPS if you engage.

It will be overwhelming. NeurIPS is a huge conference in an already large field of AI / ML. So it helps if you prepare with this advice people are giving in this thread. Don't try to attend absolutely everything, it will be too much, take some down time. But most of all, have fun and learn stuff!