How Does Duphaston Affect The Menstrual Cycle?

hi! doctor! i was advice by my doctor to take duphaston twice a day starting on my day 11 to day 25. my question is when i suppossed to have a period after i take this medicine? she told me just to regulize my period. is this medicine will help me to get pregnant? do i need to take clomid? and how will i know my fertile days? my regular cycle is 29-32 days. please advice me in preparation of my pregnancy.