Usually I would say yes, you should provide a title for your related set of fields because it is good accessibility to do so.
The standard method is to group all the fields in a
fieldset and provide a
legend within this that describes all the fields within that section of the form. This is an accessibility preference, but not a full requirement (different screenreaders treat the
legend differently (if at all)).
The reason for doing so becomes particularly useful when you have a large form with several groups of fields, because - while visually it is easy to tell one set of fields apart from another - screenreaders do not have such a luxury. By providing a
legend the screenreader will basically announce to the user that 'the set of fields you have previously been entering have completed, this next set of fields are all related to x' which makes it much clearer to the user what they are going to be expected to provide.
To quote W3C:
FIELDSET element allows authors to group thematically related controls and labels. Grouping controls makes it easier for users to understand their purpose while simultaneously facilitating tabbing navigation for visual user agents and speech navigation for speech-oriented user agents. The proper use of this element makes documents more accessible.
LEGEND element allows authors to assign a caption to a
FIELDSET. The legend improves accessibility when the
FIELDSET is rendered non-visually.
But, as I opened this post with 'usually' that means I don't think it's required in all instances. Your example above is a small form where all the fields are related to eachother, so would all therefore have the same header or
legend. Because of this you can probably get away without having the additional markup provided everything is introduced and labeled suitably. However I would probably look to include them unless it becomes particularly impractical to do so.