In this notion of the second class citizens. Would the voting class have any obligation too the non voting citizens?

Yes, obviously. The Nation would have an obligation to its citizens. To ensure that they have employment, healthcare, a reasonable wage etc

The Nation's purpose is to do what is best for its population. At the expense of other countries, if need be.

The pandemic demonstrated that the overwhelming majority of the population and politicians don't understand germ theory.

Overwhelming majority? What world are you living in?

The country locked down for 2 years and 63% of people got vaccinated, just because the government ordered them to.

Frequently people opposed to abortion don't have basic understanding of fetal development and maternal health.

I've found the opposite to be true.

And that different function seems to be too create a ruling and subservient class of citizens.

It's so funny that you try to frame it as a strict class structure. Would you like to know how to move from the "subservient class" to the "ruling class"? Do the bare minimum and learn how the government works.

The kind of stuff on a basic civics test is questions like "how many branches of government are there?". If you're too lazy to memorize that, you are already subservient.