1.667 words a day according to their tool. I did NaNoWriMo for the first time in 2018 and I won with 62k words. Last year I didn't have a project, but this year I'm ready for it!
The goal is to write every day, but if you have an off-day and then write 3000 words the next that's still good of course. It can be though, some people drop out because 50.000 words in a month is not an easy feat. But it is doable. Especially if you have support around you.
Also, the goal is not producing a perfect story, but to complete your first draft. So while you can edit while you write, the suggestion is to move the story forward every day and keep the editing for after NaNoWriMo. You won't upload the story on their website, just add the word-count of it in their tool. And if you manage to get the 50.000 you will be a NaNoWriMo winner!
For some people it helps to join regional groups, because in those people get together for virtual write-in, sprints, and just general support from others who live in the same area as you do.
And this thread is of course for everyone on this site to cheer for each other :)