30 day challenges

Anyone one done them? Results? Worth it? Because

I googled 30 day squat challenge and I found a whole group of challenges....
Burpees
Push ups
Plank
Little black dress
Lunges
Sit ups.
Many more including for beginners


Well I decided to pick 3 and do them adjusting each a bit to making the rest days on all of them on the same day. Every 4 days
I am doing
Beginners squat
Burpees
And beginners push up challenge

I went and bought a blank weekly planner. The days start on Monday so I am starting December 2nd

And I'm curious on tips insight?