% Use XeLaTeX or LuaLaTeX as compiler.
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\usepackage[skins,breakable]{tcolorbox}
\usepackage{paracol}
\usepackage{setspace}
\usepackage{fontspec}
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\usepackage{babel}
\usepackage{lipsum}
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% https://stackoverflow.com/a/56310589/19020549
\newcommand\signature[2]{% Name; Department
\noindent\begin{minipage}{10cm}
\noindent\vspace{1cm}\par
\noindent\rule{5cm}{1pt}\par
\noindent\textbf{#1}\par
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\noindent#2%
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\begin{tcolorbox}[blanker, breakable, width=\linewidth]
1600 Pennsylvania Avenue, \\
Washington, D.C., \\
USA
\noindent\vspace{4cm}\par
\textbf{Dear Sir/Madam,} \\
\lipsum[1][1-4] \\
\lipsum[2][1-5]
\noindent\vspace{1cm}\par
Sincerely, \\
\signature{Quandale Dingle}{Tlf.: 089 011 0425 \\ E-mail: quandale.dingle@hotmail.com}
\end{tcolorbox}
\switchcolumn
\begin{tcolorbox}[blanker, breakable, width=\linewidth]
{
7th of September, 2022 \\
Quandale Dingle \\
221B Baker St., \\
London
}
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\fancyhf[OFC]{\normalsize Quandale Dingle - 089 011 0425}
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