Dwarf Fortress: Area not getting designating for mining?

I’m a new player of Dwarf Fortress. I was following the Quick Start Guide here.

I’m trying to designate an area for mining but it doesn’t seem to work. According to the quick start guide, a “a rectangle will be highlighted”. But nothing of that sort is happening, and none of my dwarves start mining.

Yes, I do have mining turned on for one of my dwarves, and he does have a pick, so I am not sure what the problem is.

Here are some screenshots:

After designating the job:

The jobs menu after designating:

Solution 1:

Mining is only a designation for the current Z-Level. The world of DF is divided in slices called a Z-Level, and you need to use stairs or ramps to go from a level to another. Here, you are telling your dwarves to mine tree and open air... Not very useful

You should designate for mining in a black area like at the top of your screenshot. These areas are underground, where you can dig directly without having to go up or down.

If you really want to go down, dig one down staircase and one up staircase just bellow (use < and > to move between levels), or dig a channel, which is a kind of "dig the ground just bellow" command.