FormLayout size problem and subtitle

I have two questions regarding FormLayout.
I have two panel and in each panel a FormLayout. Each formlayout have multiple field (more than 25) that could appear or not.
Both panel are in a VerticalLayout.
1 I would like to know if it is possible to have always the same width for my the two FormLayout.
2 Is it possible to add a title or a subtile in a form layout in order to have a better render of my fields?