\setuplabeltext[en][chapter=Chapter~]

% while for chapter title this line break is handy (in my use case)
\setuphead[chapter][
        alternative=middle,
        style=\bfc,
        conversion=Romannumerals,
        numbercommand=\groupedcommand{\cap}{\blank[0.5cm]},
        after={\blank[1cm]},
        ]

% for section it is inappropriate
\setuphead[section][
        align=middle,
        style=\bfa,
        sectionsegments=section, % ignore component label
        ]

\starttext
\chapter{Foo}
\section{The First Section}
Text.
\stoptext