Good Day
How can I make the Section in 1 Form a Different Color
The section field is a field, and does not group fields in any way. If you need to separate sections of the form, I recommend using page breaks rather than sections. You can style each page of a form differently if you want, or maybe having them on separate pages with page titles is enough.
Or you can use this plugin from JetSloth that will put each section into an accordion, which also separates them.