There is a lot more to it than this, but here is a quick explanation.
A center differential has two output pinions/shafts compared to a transmission which has 1 solid shaft or spool. The two output shafts can work independently of each other by means of spider gears inside the diff cup. If you notice there will brakes on the front and the rear of the center differential. That is because you have to stop 2 independently moving shafts as compared to 1 solid shaft which would only need 1 brake setup like a standard transmission. Light wt oil/lube allows a very free action of the spider gears and a very independent action of the output pinions/shafts. Heavier oil/lube will tighten up the action of the spider gears and reduce the independent action of the outputs.
The center diff acts just like a limited slip front or rear diff. It will send the power to the wheels with the least amount of traction/grip. When you accelerate the rear squats, the front raises and with a light wt oil in the diff almost all the power will go to the front wheels because they now will have less traction than the rears which = no wheelies. The heavier the diff oil/lube you use in the diff cup the more locked the spider gears inside the diff cup become and power output from the center diff to the front and rear diffs become more equal in proportion to the wt of oil used.
Some 1/10th scale diffs use 4 spider gears, others like 8th scale use 6 and 8 spider gears.
More spiders’ means less wt oil can be used to obtain similar results as heavy wt oil and less spiders because there is more surface area of gear teeth to act against the oil wt.
Something as simple as plumbers putty or silly putty can be used in the diff cup or a very heavy diff lock lube to almost lock the spider gears together and act very similar to a solid output shaft to obtain the wheelies you are looking for with a center diff.
Some will go as far as filling the diff cup with JB-weld or epoxy to completely and permanently lock the center diff in effect making it a solid shaft/spool.