I drink 450ml of energy drink every day. now i want to stop drinking it. i feel sleepy all the time and don't have any energy. do you have any tip?

Stopping: cold turkey will make things worse but after a few days should be back to baseline. The energy drinks contain lots of caffeine and other stimulant type substances. See how you feel after a period of abstinence. Exercise and healthy diet and plenty of sleep will suit you much better.

Energy drinks: most drinks have high content of caffeine . may try to cut down the amount rather than stop abruptly.