All my variables in my widgets are not editable - why and how can i make them editable ?

Open eye is default UI for widget components in UE4. It’s not made like that.
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Your friend is using an earlier version of UE5 where they hadn’t changed this yet- like 5.0.3 or the early access versions:
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Again, though, it quite literally could not be less important on a widget. The only time you can ever even select a widget in editor is if you use the widget component- but even then you still can’t access instance editable variables.
The only reason you can even change it on normal variables on a widget is to allow you to expose the variable on spawn so you can set a default value when constructing the widget.