Shell’s built-in command usually do not have man pages, and you can try something like this:

man cd

And you will get something like this:

No manual entry for cd

But what if you still need help for a command like cd, you can use help <p class="codigo">help cd</p>

Change the current directory to DIR.  The variable $HOME is the default DIR.  The variable CDPATH defines the search path for the directory containing DIR.  Alternative directory names in CDPATH are separated by a colon (:).  A null directory name is the same as the current directory, i.e. `.'.  If DIR begins with a slash (/), then CDPATH is not used.  If the directory is not found, and the shell option `cdable_vars' is set, then try the word as a variable name.  If that variable has a value, then cd to the value of that variable.  The -P option says to use the physical directory structure instead of following symbolic links; the -L option forces symbolic links to be followed

Another option you have is to read the man page of the shell you are using, as example.

man bash