finalmente!!!! Grazie tante…
Ho risolto in questo modo
`
%\renewcommand{\familydefault}{\sfdefault}
\usepackage{titlesec}
%formato
% capitolo 1
%———-
%capitolo
%———-
\titleformat{\chapter}[display]
{\bfseries\Large}
{\filleft\MakeUppercase{\chaptertitlename} \Huge\thechapter}
{0ex}
{\titlerule
\vspace{0ex}%
\filright}
[\vspace{0ex}%
\titlerule]
%
\titleformat*{\chapter}{\bfseries\Large\singlespacing}
\titleformat*{\section}{\bfseries\Large\singlespacing}
\titleformat*{\subsection}{\bfseries\large\singlespacing}
\titlespacing*{\chapter}{0pt}{*-5}{*3}
`Ancora grazie!!
Puoi risparmiarti`\titleformat*{\chapter}{\bfseries\Large\singlespacing}`
aggiungendo \singlespacing nel primo titleformat:
`\titleformat{\chapter}[display]
{\bfseries\Large\singlespacing}
{\filleft\MakeUppercase{\chaptertitlename} \Huge\thechapter}
{0ex}
{\titlerule
\vspace{0ex}%
\filright}
[\vspace{0ex}%
\titlerule] `
Ciao