\documentclass[12pt, a4paper, oneside]{book}
\usepackage[utf8]{inputenc}
\usepackage[backend=biber,style=alphabetic,sorting=ynt]{biblatex}
\usepackage{microtype}
\addbibresource{references.bib}
\usepackage[ngerman]{babel}
\usepackage{csquotes}
\usepackage{subcaption}
\usepackage[hidelinks]{hyperref}
\usepackage{acronym}
\usepackage{graphicx}
\graphicspath{ {./images/} }
\usepackage{fancyhdr}
\setlength{\headheight}{15pt}
%\linespread{0.4}
\def\whatIsIt{Bachelorarbeit}
\def\title{Erweiterung von Irgendwas}
\def\fakultaet{Wirtschaftswissenschaften}
\def\author{Max Müller}
\def\addrLineEins{Muster Straße 1}
\def\addrLineZwei{PLZ, Ort}
\def\matrikelNr{1234567890}
\def\location{Essen}
\def\date{01.01.2021}
\def\betreuer{Betreuer Name}
\def\ersterGutachter{Prof. Dr. Name}
\def\zweiterGutachter{Prof. Dr. Ucker}
\def\fach{Fach}
\def\semester{Wintersemester 2020/2021}
\begin{document}
\include{title}
\frontmatter
\tableofcontents
\listoffigures
\listoftables
\include{acronym}
\include{abstract}
\mainmatter
\lhead{}
\chead{}
\pagestyle{fancy}
\include{chapter1}
%\include{chapter2}
%\include{chapter3}
\printbibliography[heading=bibintoc]
\appendix
\include{appendix}
\newpage
\include{erklaerung}
\end{document}
