If you're actually tired with no sleep and are drowsy then you really need to sleep.
If you have trouble sleeping try some sleeping pills that you can get over the counter.
Or try sniffing or breathing in some essential oils such as Chamomile or lavender Essential Oils or use the essential oils in a diffuser.
Those essential oils can help you sleep at night.
If you do need to fight drowsiness then try taking a quick nap of around 5 to 10 minutes and then try drinking some coffee or energy drinks.
If you're actually tired and drowsy then it can be hard to stay awake.
If you are drowsy then make sure you do not drive or operate any machinery as it can turn deadly.