\documentclass{article}

% content related packages
\usepackage[os=win]{menukeys}

% layout related packages
\usepackage{parskip}
\usepackage[a4paper, margin=.9cm]{geometry}
\usepackage{pdflscape}
\usepackage{multicol}


% TODO show the mod key in a diferent way, maybe shortend as "mod" or darker like the example
\newcommand{\mod}{\ctrl + B}
\newcommand{\tkeys}[1]{\keys{\ctrl + B + #1}}

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\begin{document}

\begin{landscape}
\begin{multicols}{2}
\begin{minipage}{\columnwidth}
    
\section*{sessions}
\subsection*{new sessions}
tmux,
tmux new,
tmux new-session,
tmux new -s sessionname
\subsection*{attach sessions}
tmux a ,
tmux attach,
tmux a -t sessionname
\subsection*{remove sessions}
tmux kill-session -t sessionname
\subsection*{key bindings}
\tkeys{\$} rename \\
\tkeys{D} detach \\
\tkeys{(} next \\
\tkeys{)} previous \\
\end{minipage}
\begin{minipage}{\columnwidth}
\section*{panes}
are the sections that make up a window
\subsection*{key bindings}
\tkeys{\%} vertical split \\
\tkeys{''} horizontal split \\
% this was shortened
% TODO fix this odd looking combination of arrows
\tkeys{\arrowkeyup, \arrowkeydown, \arrowkeyleft ,\arrowkeyright} move to pane (up,down,left,right) \\
\tkeys{O} go to next pane \\ % that is an O, the letter, not a number
\tkeys{;} go to last active pane \\
\tkeys{\}} move pane right \\
\tkeys{\{} move pane left \\
\tkeys{!} convert pane to window \\
\tkeys{X} kill pane
\end{minipage}
\end{multicols}

\vspace*{\fill} % Pushes the next minipages to the bottom

\begin{multicols}{2}
\begin{minipage}{\columnwidth}
\section*{windows}
are like tabs and occupy the space of a session screen
\subsection*{key bindings}
\tkeys{C} create window \\
\tkeys{N} move to next window \\
\tkeys{P} move to previous window \\
\tkeys{L} move to most recent window \\
\tkeys{0..9} select window by number \\
\tkeys{'} select window by name \\
\tkeys{.} change window number \\
\tkeys{,} rename window \\
\tkeys{F} search window \\
\tkeys{\&} kill window 
\end{minipage}
\begin{minipage}{\columnwidth}
\section*{copy mode}
\subsection*{key bindings}
\tkeys{[} enter copy mode \\
\tkeys{]} paste from buffer

\subsection*{copy mode commands}
\keys{\SPACE} start selection \\
\keys{\enter} copy selection \\
\keys{\esc} clear selection \\
\keys{g} go to top \\
\keys{G} go to bottom \\
\keys{hjkl} move cursor (left,down,up,right) \\
\keys{/} search \\
\keys{\#} list paste buffers \\
\keys{q} quit
\end{minipage}
\end{multicols}
\end{landscape}

\end{document}