Zelda-like conversations

Hello!
I am currently in the process of making a game and I am thinking of a way to do conversations that appear, letter by letter (kind of like in Zelda or similar games). I do not have the money to buy an asset from the store, so I wonder if anyone knows how to make a conversation like this?

not tested, but this is more or less what you are looking for.

string fullText = "your zelda like text here";
string displayText = "";
float typeDelay = 0.3f; // just an estimate
int nextCharacter = 1;

Update(){
    if (nextCharacter <= fullText.length){
        displayText = fullText.subString(0,nextCharacter);
        YourTextBox.text = displayText;
        nextCharacter++;
    }
}

Once again, I feel very stupid and I feel like I am missing something completely obvious, but here goes;

I have included a screenshot of the hierarchy and the text inspector, I will also include the slightly edited code, nothing that should matter.