Get a widget from an actor class C++

hello, how can I get UTextBlock to create within my UUserWidget class from another script? I want to get UTextBlock in my AActor class.

Here is an example:

so I get any variable or component from a class gameinstance in my actor class:

UMyGameInstance* GameInstance = Cast<UMyGameInstance>(GetGameInstance());

GameInstance->YourComponent

so I get any variable or component from a character class in my actor class:

APlayer* MyPlayerCharacter;
for (TActorIterator<APlayer> ActorIt(()); ActorIt; ++ActorIt) {
	MyPlayerCharacter = *ActorIt;
	MyPlayerCharacter->YourComponent
	break;
}

I just want to change from my class AActor the text of my UTextBlock hosted in my UUserWidget class since I have to use SetText

You can find widget tree of UUserWidget from this property:

and there you got ton of different functions you can use: