Check out the View::share documentation. https://laravel.com/docs/8.x/views#sharing-data-with-all-views If that is not what you are looking for, then I would suggest, inside your controller, set a session variable like this.
Above foo is the name of the variable and bar is the value. Now, when I need to change the value of foo, for example in a blade file, I can do so like this.
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