Question

how I can use the second argument of previous command in a new command ?

example, with

$ mkdir test 

I make a directory, how I can use the name of directory for change to this ?

$ mkdir test && cd use_var

Answer 1

With history expansion, you can refer to arbitrary words in the current command line

mkdir dir1 && cd "!#:1"
# 0     1   2  3  4

!# refers to the line typed so far, and :1 refers to word number one (with mkdir starting at 0).

If you use this in a script (i.e., a non-interactive shell), you need to turn history expansion on with set -H and set -o history.