Do as many of these as you need to but it's recommended to keep a limit between 9 and 11 pomodoros per day (about 3 sessions). The original pomodoro technique says that you could also take a break every 25 min, which is about the length of the smallest deep work session timer on the Fabulous app. It's up to you if u wanna do this too. I recommend you use a timer to remind you when to stop. You can chain 3 of the Fabulous deep work 25 min timers with 5 min breaks in between, or then set a timer for 1h 30min and then have a 30 min break.
That's all hope it helps!