Hello!
Thanks for the excellent question. The short answer is yes, and no.
The HTML for your WordPress website comes from two main sources, the content and the theme.
The Post and Page Builder works with the content of your web pages, and you can use either Visual or Text editing mode. In text mode, you can change the HTML layout of your content, as demonstrated in these two screen shots:
Editing the HTML for the Theme, however, is a little more complicated. This is because the HTML is generated by PHP code, and this is what makes WordPress so customizable and flexible. However, it does take more advanced programming knowledge to make adjustments. If this interests you, I suggest checking out our documentation on creating child themes for BoldGrid.
I hope this helps!