Buttons to display blocks

I remember that @Eldar already explained something similar but I can not find it any more and I hope someone can help me.

I have to create texts or buttons that make only what they indicate visible.
Text “A” makes visible only the bric “A”, text “B” makes visible only the bric “B”, etc.

Are you searching for toggle visibility?

more or less … I saw in the link you sent me that there is something but it is a complex and long code …
In practice I have to show only what I click “A”, “B” or “C”. If I click on one the other must disappear.

Thats something I want to achieve as well. I wrote a question about this in another post. So far no answer (yet).

see: Button changed when pressed and toggle visibility