On the section titles, there is no possibility integrated in BF.
It is necessary to note the class of the sections and to place a css rule in the css file of the used theme.
For the fields, for info:
In the field properties, you have to check the "Required" box but be careful, this only adds the star, to make the field really "required", you have to test if it has content and eventually what content.
To do this, you just have to choose a validation type "Library" and choose a validation script corresponding to the content expected in the field:
Non-empty = FF::ff_valuenotempty
Email = FF::ff_validemail,