Well it's safe to say that's where ground and neutral connect lol.. like 20 times over
you got 2 different bars there and then on the top 2 larger lugs for the main ground / main neutral
and then some second smaller aluminum one
I'm guessing the bar underneath these two are connecting the two together
View attachment 206379
as for your second box.. sub panel..
they should be separate
You should have a second bar in there and use that as your ground as it screws directly into the box
your current bar is not connected to the box
(THAT IS CORRECT), the connection screw is here:
View attachment 206380
So
don't screw anything in that one..
basically yours should be the same as mine, white on top and copper grounds on bottom or wherever you put your bus bar (there are 4 places for it)
however unlike mine, don't put a screw in that hole
and probably don't spray spray foam all over the box like some guy did either
View attachment 206383