CSS with Rich Text Editor

I am trying to add CSS in my text but I am not able to do it.
So basically I have a Form which is Rich Text Editor and the user can write on it and it gets saved in the database.
Now, I am fetching the saved data and displaying it in the form of text but I want to apply CSS on certain elements like h2,h1, etc., but I cannot do so.

Any help with appreciated.

Bubble’s Rich Text Editor saves in BBCode. Here’s a sample of how it’s saved in the DB:

[h1]Title Here[/h1]
Welcome to the body text

Bye Link!

You’re going to either use a plugin to convert it to HTML, figure out your own JavaScript to convert it, or use the myriad of RTE plugins that already support HTML. You can check out Quill Rich Text Editor Plugin | Bubble.