who are "we" in "we the people"?

It did not include slaves, native americans, wildlife, domestic animals, plants, minerals, active volcanic regions, deep sea trenches, women, or children. Like obviously, dude. Is the source of your confusion your ignorance of the zeitgeist? Wow.

Basically

at that time

"we the people" included

- free adult male residents of the U.S.

- excluding Native Americans

It did not include

- women

- children

- slaves

- Native Americans

Clearly

at the time

they did not consider ALL of the so-called "inalienable rights" to be universal.

For example: the Declaration identifies these three as "unalienable rights"

- life

- liberty

- pursuit of happiness

and clearly the second was not afforded to slaves, either in the time of the Declaration nor in the time of the Constitution's adoption by the colonies (states).

Fortunately

the meaning has changed over the centuries

and now we interpret it as including at least all U.S. citizens

some would say: all U.S. residents, citizen or not, legal or not.

We the people are American citizens. Those not included in that category have human rights.

the modifier "of the United States" implicitly excludes everyone living here who is not a citizen [because their allegiance is to some other nation].

Us...................................

We means we.....all of us.