1 = 
2 =
3 = PolyQuilt addon for Blender 2.8
4 = The grid is poor
5 = There’s no such thing afaik. If you want to select through you need to painfully go to the wireframe/x-ray mode (shift + z)
6 =
7 =
8 = shift + r, I believe
9 =
10 =
11 = The N panel has something, I guess
12 = Impossible