Pomodro clock ,how to manage state according to const in the render

Hello campers I am really frustrated , I don’t know how to change the state according to a variable saved as a const in the render method ,in my code there is a component called SessionAndBreak where the render method runs two element conditionnaly the second runs after the first
I want to render the second element and put on it setInterval ,so I don’t know what condition I can use to achieve that .

here is my code pen link