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I strongly suggest that you try GDScript, it's sooo easy and I (for real) think that it's easier to make scripts using GDScript than in VisualScript, beside that in GD you can keep things more organizated and you can do more in less time since you don't have to connect lines and etc.
For exemple, what you want to do you could do in GDScript just by typing
$YourLabelName.text = "the new text".
I really recommend this course on Udemy, I saw it myself and I can say that its really great; it goes from the very very basics to more advanced stuff, it's totally worth the $20.