How to run TCl to do operation in Quartus II?

--- Quote Start ---

as my understanding, we use Tcl in Quartus is for operating Quartus (pin assignments, project compile, static timing analysis.....), not for design, right?

--- Quote End ---

That is correct.

TCL = Tool Command Language

Its a language for controlling (scripting) tools.

You write your code in VHDL, you write timing constraints in Tcl (in an .sdc) file, you can manage the Quartus and Modelsim project build sequence using Tcl, and you can post-process timing analysis results using Tcl.

Cheers,

Dave