Birth control


so i just started birthcontrol (the pill) and i have it in a packet of 21 pills. my cycle usually last around 30 days and i was wondering if i’m not supposed to take the pills for a week and then start a new packet? i thought i would have to take one pill everyday so when i would run out i would just open a new pack and not have to wait another week. can anyone explain or help? thank you!!