How can I lose 5 pounds by December 7th to pass my height and weight?

Another thing that I did many years ago to drop weight -- STOP ALL SALT and SUGAR for the time being, NO French fries, NO sweet drinks or on cereals. I lost 10 pounds in 30 days after returning from South Korea.

Stop drinking beer or any other alcohol. For most people below 30 that alone will get you below 20% bf

A lot of good advice here, especially eliminating salt, alcohol and processed foods.
I will warn you in advance that if you are struggling to achieve maximum allowable weight now, you are likely to continue to struggle. I understand the need to cut a few pounds to get through MEPS, but it doesn't end there. At 5'6" and 159 lbs you are going to have to change your body composition completely or you will end up in a constant state of misery trying to stay in regs.
My suggestion is to get down under your weight limit and see how hard it is to maintain it through the winter. If you can't do that, you may want to consider another career choice.
This advice is coming from a barrel chested, short legged Marine who struggled most of my 21 years to maintain weight requirements.

Low carb diet and tons of water.

I can drop 10 lbs in 2 weeks by eating broccoli and packets of tuna for my meals and drinking over a gallon of water a day.

Get used to crash diets in the army. I end up having to do one every time we need to do height weight. Can pass my ACFT no sweat just have a long neck and long upper torso so taping is always awful for me. Frustrating to see the guys with big beer guts with fat necks pass tape but can’t pass a PT test. Oh well that’s the way the test is done.

Good luck!

Only eat 1 meal with no carbs and drink only water. The weight will fall off.

I have had the best results with Keto diets. That means very restricted carbs and switching most of your calories to healthy fats and proteins. Generally the switch will make you lose 5 lbs. fairly rapidly since you will not retain water like you do eating carbs. Lot's of Keto advice on the Internet.
My post Covid 19 lockdown weight got up to at least 285 (at that point, I just didn't weight myself anymore). Thanksgiving of 2020 I started on a serious program to get my old (65 at the time) and out of shape ass back in condition. With a couple of short periods of backsliding, in that year using Keto and getting serious about a workout program again, I am down to 235. I have a weight lifters build, so that puts me about 23% body fat. Goal body fat is 18%. Another full percentage by Christmas!!.

Wrap your stomach in plastic wrap and go in the sauna in your winter pt clothes a few hours a day until your weight in.

Have in mind that a lot of responses below are short-term solutions. Exercising is a way to stay fit, but diet will be the way which will make you get to the right weight. Cut on carbs (including, sweets and alcohol, no fast food). Please don't feel shy to message me if you need advice or encouragement.
Be very strict with water intake. I still struggling to drink enough water, and my body tends to keep that "water weight" ( oh no I'm going to die from dehydration, let's keep at that water inside just in case), my weight can change 5lb within the same day.

Also if you 5'5' pushing towards 5'6', which is my case too, so it's is very important that they measure your height properly. Improper measuring techniques can cut that half on an inch needed to be in the next weight bracket. Army weight standards are very outdated, so even the person who is fit, still can be "fat". Believe me, all these pounds will be shed in BCT

The easiest way to lose weight is to always leave the table a little hungry while cutting out all high calorie snacks. If you are really hungry, eat some celery sticks or an apple.

fast three days eat 2 days and repeat till weight is gone