I've seen these challenges a few times now. You'll be really sore for the first 2-7 days then you'll get used to the training volume.
What is your goal with this habit? You won't be progressively overloading so past day 5-7 you'll stop inducing muscular hypertrophy (no gains) and just become better at pushup endurance.
If your goal is to get more defined and stronger I'd start with less reps and work up, progressively getting harder. You can also check out different, more difficult, variations too.