wish
and tclsh
programs, and documentation.
You need to double-click on the tcl830.exe file to start the installation procedure (a big blue screen). Just follow the default installation instructions by clicking on [next], [finish] in the subsequent dialog boxes.
If that all goes well, then you should have a working file association, which tells Windows to access the wish80.exe application whenever it's asked to open a .tcl file. Files with the .tcl suffix should be displayed with a red 'Tk' icon.
See Tcl/Tk Core Download Page for further details on obtaining the source release.