Ok so Im making a map where ultralisks attack. I want it to be so when Force 1 kills X amount of ultras the next wave comes but the next wave has 2 more ultras than the previous one. How do I do that?

This isn't really binary count-offs, unless you plan on having more than like 20 spawning at once, you have a death count hold the current number of ultras, then have a trigger that subracts 1 death and creates an ultra, also make sure you add 1 death count to a temporary storage death so you can add to it later, copy those triggers a few times and it should work perfectly.

Do you understand how Binary Count-Offs work in theory, or do you need help with that too?

Well I don't know how Binary Countoffs work or death counts lol. Never had to use them.

Read some tutorials on Death Counts and Binary Count-Offs, it will greatly help your mapping as they are the key component to the most complex maps.