Theme export warning The theme doesn't have the index page

I selected a block from Foundation 6.5 library to add and saved as paint.html in my mcgraphics.us/art project. Everytime I try to close paint.html I get a popup saying “The theme doesn’t have the index page. Each WordPress theme needs the index.php template.” And “The theme doesn’t have Master page.” I’m forced to quit Pinegrow to close paint.html.
mcgraphics.us/art/paint.html seems to work.
I don’t know WP though I have Pinegrow Pro WP.

I’m totally new to PG, but not to software development. I would like you to try this…

If you have an index.php file then either copy that to index.html, or create a totally blank index.html file with nothing in it to get rid of the nagging.

What I would say is that there possibly might be a place in the PG software to turn off the index.html requirement, but I don’t know.

Did you read the documentation? I usually won’t start anything without skimming most everything first.

Hopefully someone who knows better than both of us will say something and we will both learn.

What I need to know is whether I’ve acident made WP by using foundation 6.5 and if so how do I convert to a non WP page. I’ve done video tutorials for years and just seem to get further behind.