\documentclass[a4paper]{scrbook}
\usepackage[utf8]{inputenc}
\usepackage{graphicx}
\usepackage{booktabs}
\usepackage{url}
\usepackage{relsize}
\usepackage{hyperref}
\usepackage{libertine}
\usepackage{ifthen}
\usepackage{fancyhdr}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Replace these values
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\newcommand{\thesistitleDE}{Deutscher Titel\\Maximal zwei Zeilen}
\newcommand{\thesistitleEN}{English Title\\Two lines at most}
\newcommand{\student}{Firstname Lastname}
\newcommand{\matrnr}{123456}
\newcommand{\stammnr}{234567} % Unset this variable if you only have a (single) matriculation number
\newcommand{\submissiondate}{XX.\ Monat 20XX}
\newcommand{\supervisor}{Prof.~Dr.~Rehrnert}
\newcommand{\secsupervisor}{Prof.~Dr.~Zweitprüfer} % Unset this variable if no second supervisor is required
\newcommand{\faculty}{Angewandte Informatik}
% Select your course of studies here
%\newcommand{\studies}{Bachelor Cybersecurity}
%\newcommand{\studies}{Bachelor Künstliche Intelligenz}
\newcommand{\studies}{Bachelor Angewandte Informatik}
%\newcommand{\studies}{Master Angewandte Informatik}
%\newcommand{\studies}{Bachelor Elektro- und Informationstechnik}
%\newcommand{\studies}{Master Elektro- und Informationstechnik}
%\newcommand{\studies}{Bachelor Medientechnik}
%\newcommand{\studies}{Master Medientechnik}
%\newcommand{\studies}{Master of Applied Research}
% Select the targeted degree here
\newcommand{\degree}{Bachelor of Engineering (B.Eng.)}
%\newcommand{\degree}{Master of Engineering (M.Eng.)}
%\newcommand{\degree}{Master of Science (M.Sc.)}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\renewcommand*{\UrlFont}{\ttfamily\smaller\relax}
\begin{document}
\pagestyle{headings}
\pagenumbering{roman}
\input{title}
\input{declaration}
\chapter*{Abstract}
\addcontentsline{toc}{chapter}{Abstract}
The abstract goes here
\tableofcontents
\cleardoublepage%
\setcounter{page}{1}
\pagenumbering{arabic}
\input{main}
\bibliographystyle{IEEEtran}
\bibliography{references}
\end{document}