It's a very common question(s), don't worry. RAM can sometimes be a complicated subject, especially when it comes to overclocking.
As for your first question, Yes it does, since it is also DDR4 (DIMM 288). Be aware that for compatibility reasons, RAM gets checked by the vendor to verify an optimal operation, written down in the Memory QVL (Qualified Vendors Lists) https://www.asus.com/ch-de... . That being said, technically any RAM that is DDR4 (DIMM 288) should work. If it's not listed, it just means that they didn't test this RAM personally in their labs or are just not necessarily guaranteeing your RAM to work perfectly, although it should since it's the suiting memory for it and if not, I'd make a complaint.
Secondly, yes, the number in DDR4 XYZ is the maximal officially supported overclock, meaning that the RAM itself should be able to operate at that speed, even though it is more than the technical specs for DDR4, which is 2133Mhz. As for the motherboard, ASUS usually limits your boards max overclocking choices in the BIOS of the respective motherboards, meaning that in this case, you will be able to run your RAM at a maximal speed of 3600Mhz.
So, yes, 3600Mhz is the maximal overclock. (Note that this depends on the CPU you use, check the website for the specs.)
That's a good observation: Yes, it is also possible to use a lower speed, therefore mostly cheaper RAM, but this comes at a drawback. The lower speed RAM might not necessarily be up for an overclock over its specs, leading to crashes and data corruption. But yes, depending on your luck and quality of your product, it is sometimes possible to buy 3466Mhz RAM and let it stably run at 3600Mhz without any troubles. I'd recommend you though to run the RAM just in its predefined speed, as this should not come with any trouble or advanced RAM capability testing, since you're new to PC building.

A customer write us;

I'm not a geek either. I'm not particularly interested in overclocking as I'm not a gamer. I just want good and reliable ram. So, here's what I know:
3600 is the maximum transfer rate. In this case the unit is MT/s - I should think. MT/s = mega_transfers / second. It refers to the number of operations per second while transferring data.
Hope that helped.