How do I download old plugins?

I have an old project in c2, but I want to convert it to a c3 file, but before that in the addon manager I need to load old plugins and behaviors that should be present in the project. These plugins seem to have been purchased with the game, but I don’t understand how to add them, or tell me where I can download such plugins

ok, but how can I add such old plugins and behaviors to c3? Construct 3 itself recommends the old version on which I should install these plugins, but another problem is that it doesn’t see them, what should I do and how to add them to the runtime environment ?

You can't use C2 plugins in C3.

what does this error mean, I loaded all these plugins into the folder with the construct 2 program, but nothing works and how to fix it. I realized that this will not work on C3, I want to open the project in C2, but the plugins from your site do not work

rex_chess is a behavior, it needs to be in Behaviors folder, not in Plugins.