Change a template Chapter Layout

Question

I am using this Overleaf template provided in template link

They given:

I want to change to this chapter layout:

Is it possible? I cannot find out where they do the setting for this.

They main.tex file:

\begin{document}

% Title page
\include{structure/title}

% All subsequent pages must be numbered, title page is considered page i,
% front matter is numbered in lowercase Roman numerals
\pagestyle{fancy}
\pagenumbering{roman}
\setcounter{page}{2}
\doublespacing

% Dedication (optional)
\include{structure/dedication}

% Acknowledgments
\include{structure/acknowledgements}

% Abstract
\include{structure/abstract}

% Table of Contents, List of Tables, List of Figures
\tableofcontents

%List of Tables & Figures
\include{structure/tablesfigures}


%%%%%%%%%%%%%%%%%%%% DISSERTATION CONTENT %%%%%%%%%%%%%%%%%%%%

% Regular numbering starts now, first page of first chapter is page 1
\clearpage
\setcounter{page}{0}
\pagenumbering{arabic}

% Body


\include{chapters/01-introduction}

\include{chapters/02-background}

\include{chapters/03-chapter}

\include{chapters/04-chapter}

% References
\clearpage
\addcontentsline{toc}{chapter}{Bibliography}
\markboth{\MakeUppercase{Bibliography}}{}
\singlespacing
\printbibliography

\appendix
\include{chapters/99-appendix}

\end{document}

Answer 1

I will be happy to remove this but maybe

\documentclass[12pt,oneside]{book}
\usepackage{titlesec}
\titleformat{\chapter}[block]
  {\normalfont\sffamily\huge\bfseries\filcenter}
  {\filcenter\chaptertitlename\ \thechapter\filcenter\\}{20pt}{\Huge}
\begin{document}
\chapter{Study 1: Study about \LaTeX}
\end{document}  

gives you what you want. As I wrote in the comment, it is impossible to test this in your document, so all I did is to get the class from the link, and to use it in the answer.