why don't I have Style and CSS options?

why don't I have those options?

only "themes" and "custom"...

It seems you are using card form layout (single question per page). Please note that Style and CSS tabs are only available in general classic layout (all question in one page). If you want to use that feature you can switch the form layout to classic.

Here is the guide: How-to-Change-Form-Layout

So there is no option to change the font size in a card form?? It dos't
make sense... its tiny ....
...

Unfortunately, it is not possible to change the font-size in the card layout. If you want to increase font-size you can switch to classic layout.