How does positioning work?

I’m trying to layout sprites in a simple 2D scene. I was able to get the background image and the top HUD image. Although, I don’t know if I’m doing it right.

It seems the screen range is 5 to -5 and the width is 10 to -10 (in landscape). Is this accurate?

When trying to place a sprite a long the bottom, I can’t seem to get it right. Is there a way to change the anchor point on the sprite to the left bottom?

Typically, 2D screen range depends on the orthographic Projection transform of the camera… if you set it to Identity, the coordinates will range from -1 to +1 in both directions, which causes a square object to appear stretched horizontally / aspect ration is being ignored. If you play with the ortho projection, you can make your screen range be anything you want.
(I’m pretty sure its -1 to +1, but it may be +/- 0.5 … been a while since I worked in 2D)