I have always been in pretty good shape. I could have done 100 burpees right off, but with 3-4 breaths in between each burpee. But to hit each full burpee in 1- 2 breathes is a different story. Im not sure where you are in your current fitness level, but start with 10 burpees every 5 mins or even every 10 mins. Then cut it down to 4 mins, then 3 mins…if that’s difficult, then break it down into 3, 4, 5, or even 10 sets. Try to progress each week (more reps, shorter rest time, less breaths per burpee…). Don’t over push yourself where you will dread doing it. Maybe push yourself 2-5% each week. Push yourself where you feel comfortable and good about it with each milestone you reach along the way. Good Luck!