Making it easier to install Discourse as a PWA

I can’t seem to get this to work. Admittedly new to all this.

I loaded up the component, added the js to the header, set the component to the default theme.

But then the HTML script – is it possible to have HTML in a post? It doesn’t seem like it. If not, where can I actually usefully put it?

Thanks! Really hoping this could help me.