\documentclass[a4paper, fontsize=11pt]{scrartcl}
\usepackage[absolute,showboxes]{textpos}
\usepackage{graphicx}
\usepackage[ngerman]{babel}
\usepackage[T1]{fontenc}
\usepackage{selinput}
\SelectInputMappings{
	adieresis={ä},
	germandbls={ß},
}

\usepackage{geometry}
\usepackage{helvet}
\renewcommand{\familydefault}{\sfdefault}
\usepackage[onehalfspacing]{setspace}
\usepackage{pdfpages}
\geometry{
	left=2.5cm,
	right=2.5cm,
	top=2.5cm,
	bottom=2.0cm}

\begin{document}
	
	\includepdf[]{Deckblatt}	
	
	\singlespacing
	\vspace*{-\headsep}\vspace{-\headheight}
	\noindent
	\begin{figure}
		\includegraphics[width=.333\linewidth]{BLABLA}
		\label{BLABLA}
	\end{figure}
	\\[-11ex]
	
	\hspace{70mm}
	\textit{Autor1 \hspace{20mm} Datum: \today}\\[-2ex]
	
	\hspace{69,5mm}
	\textit{Autor2 \hspace{22,5mm} Gruppe: }\\[+2ex]
	\rule{\linewidth}{1pt}
	
	\tableofcontents
	\pagestyle{empty}
	
	\newpage
	\singlespacing
	\noindent
	\begin{figure}
		\includegraphics[width=.333\linewidth]{BLABLA}
		\label{BLABLA}
	\end{figure}
	\\[-15ex]
	
	\hspace{70mm}
	\textit{Autor1 \hspace{20mm} Datum: \today}\\[-2ex]
	
	\hspace{69,5mm}
	\textit{Autor2 \hspace{22,5mm} Gruppe: }\\[+2ex]
	\rule{\linewidth}{1pt}
	\pagestyle{plain}
	\pagenumbering{arabic}
	
	\section{Einleitung}
	Einleitender Text...
	
	
\end{document}