Dialogue et personnalisation

Small questions, I am currently following the French tutorial tutounity to create a game without coding, inspired, similar to the tutorial model created by Unity with the pink character who jumps on platforms. But I would like to add to this game, dialogues presented in bubbles or other to create a serious game, questions and answers. I am a novice. Can you advise me a method, an extension that works on a Mac computer? I tried Yarn spinner but I get stuck at the first line of test script that doesn't appear and I can't edit. I would like to try something else. I saw ink spinner and VN creator , but do you know modules with integration, easy installation, to add dialogs, like Bolt for creating nodes? I have another question, which will certainly seem a little silly to you, but I dare anyway. Is that at the end of the tutorial of tutounity, we can replace for example the game object player by a character of his choice, the decoration of his choice, while keeping the link with the nodes and scripts created for the implementation of the Game? Thank you very much for your advice!