There is a TableOfContent, a ListOfFigures and a ListOfTables.
The LOF and the LOT are on one page in two columns (multicols). They should have short names as Headline ("Figures" and "Tables") In the TOC they should shown with two entries ("List Of Figures" ans "List Of "Tables"), of cause the have the same pagenumber ;-) The Headmark on their page should have the description "List of Figures and Tables"
\documentclass[12pt,DIV=10,ngerman,headings = normal,listof = totoc,bibliography = totoc,index = totoc]{scrreprt}
\usepackage[utf8]{inputenc}
\usepackage{multicol}
\usepackage{geometry}
\setlength{\topskip}{\ht\strutbox} % behebt Warnung von geometry
\geometry{paper=a4paper,left=30mm,right=30mm,top=35mm,bottom=30mm,headheight=30mm}
\usepackage[automark,headsepline=1pt]{scrlayer-scrpage}
\clearpairofpagestyles
\pagestyle{scrheadings}
\automark{chapter}
\automark*{section}
\ihead{\headmark}
\renewcommand*{\chapterpagestyle}{scrheadings}
\begin{document}
\addcontentsline{toc}{chapter}{Table Of Content}
\tableofcontents{}
\newpage
\begin{multicols}{2}
\addcontentsline{toc}{chapter}{List Of Figures}
\renewcommand{\listfigurename}{Figures}
\label{Figures}
\listoffigures{}
\vfill\null
\columnbreak
\begingroup
\let\clearpage\relax
\addcontentsline{toc}{chapter}{List Of Tables}
\renewcommand{\listtablename}{Tables}
\label{Tables}
\listoftables{}
\endgroup
\end{multicols}
\chapter{Chapter}
\section{Section}
\begin{figure}[h]
\caption{figure ONE}
\end{figure}
\begin{table}[h]
\begin{tabular}{l}
\end{tabular}
\caption{Table ONE}
\end{table}
\end{document}