Are the websites the AI builds mobile friendly, and how do I redesign only part of a page?

Yes. Everything the AI builds is normally mobile friendly, so you usually do not need to ask for it. One of the AI's steps is to test the site on mobile, and you will see it taking screenshots to make sure it works well on a phone. In the editor you can also preview how a page looks on a phone or tablet using the device view.

If an old or imported site does not display properly on a phone, tell the AI to rebuild or redesign it inside Votel and the new version will be mobile friendly.

If you like part of a page but not the rest, tell the AI to keep that part exactly as it is (clone it, keep the same code) and redesign everything else. If you do not like a color it chose, change it in the website builder, or adjust your prompt and let the AI create it again. If hero text is hard to read over an image, say exactly what you want, for example: make the image take up the whole hero section and put the text in white next to the subject.