\documentclass{article}
\usepackage{fontawesome5}

\begin{document}

% Conceal these
\faFile
\faIcon{file}
\faIcon[regular]{file}
\faIcon[solid]{file}
\faFile*
\faIcon*{file}
\faIcon*[regular]{file}
\faIcon*[solid]{file}

\faIcon{500px}

% Don't conceal these
\faFil
\faFilea
\faIcon{fil}
\faIcon[regula]{file}

\end{document}