Your plan is stupid. Especially if you are young you should sleep a minimum of 7 hours per day. Adapt your schedule and fix your priorities but the solution is not to sleep less. Otherwise: cocaine probably.

Fix lack of planning first, don't sacrifice your sleep time.

Sacrificing sleep time will affect your cognitive performance and increase risk for a lot of diseases. "There simply isn't time" is usually an excuse used when you have poor time management skills, you can try an exercise of writing down what activity you have done each hour segment. This will allow you to be mindful on which activities are wasting your time.

Polyphasic sleep schedules are also not recommended, Huberman has a good episode on sleep w/ Matthew Walker: https://youtu.be/gbQFSMayJxk

Not that I'd recommend doing this, but back when I was younger, I had the not so bright idea that I could go to work come home, game the whole night, then go back to work. It was a terrible idea in hindsight, but I used to it a lot. To achieve this, I used to mix energy drinks and pre-workout to stay awake, and I'd drink it as though I was drinking water, so I ended up drinking a butt load. I just want to stress again though that I'd never recommend actually doing this though unless as a last resort, but even then I'd caution away from it. I get there are times when one feels they absolutely must stay awake, God knows the amount of times I accidentally slept through something, and ruined relationships, but as others have said planning is probably the issue you're facing.

When I was studying a lot, I would just slowly eat saltine crackers. Most adults can't fall asleep while eating.

I had a very intense year of school one year and I gained some weight because of this method. Everything has a consequence.

If you're going to go without sleep, try a power nap here or there to help.

I used to be like you. Young and wild, being a night owl living in a world ruled by daywalkers.

Nowadays, I tend to value even an hour of sleep over staying up the whole night. You always feel better after sleep and even a little bit is better than none.

For staying up, I recommend coffee or chocolate-covered espresso beans (very easy to over-do it on these).

For waking up after only a short amount of sleep, set multiple alarms about 3-5 mins apart for about 45 mins. If you use your phone as an alarm, put your phone in an empty coffee mug to help amplify the sounds and vibrations of the alarm. There’s no guilt worse than over-sleeping when someone is relying on you.