Hi Mohammad,

FIJI (Fiji Is Just ImageJ) is probably better because it allows for more plugins. Here's the download link for it: https://fiji.sc/

Regarding the IHC Toolbox:

You can download it from the site below.

https://imagej.nih.gov/ij/plugins/ihc-toolbox/index.html

You should download a ".jar" type file named IHC_Toolbox.jar. After downloading, be sure to move the file into your .jar file to the plugins folder located here: fiji-win64\Fiji.app\plugins

Good luck!