special formatting of enumerate

Maybe something like this (margin narrowed for demonstration):

\documentclass{article}
\usepackage{enumitem}
\textwidth=1.5in
\begin{document}
\noindent This is some text before the list
\begin{enumerate}[itemindent=17pt, leftmargin=0pt, label=(\arabic*)]
\item This is an item on the first level and has a run-in label
\item This is an item on the first level and has a run-in label
  \begin{enumerate}[itemindent=0pt, labelsep=10pt, leftmargin=20pt,label=\alph*)]
  \item This is an item on the second level and looks more familiar
  \item This is an item on the second level and looks more familiar
  \end{enumerate}
\end{enumerate}
\end{document}

\documentclass{article}
\usepackage{enumitem}
\usepackage{showframe} % <---- remove in actual document.


\setlist[enumerate, 1]{label={(\arabic*)}, wide=0pt, widest=99, labelsep=15pt}
\setlist[enumerate, 2]{label={\alph*)}, align=left,labelsep=*}
\begin{document}

This is some text before the list. This is some text before the list. This is some text before the list. This is some text before the list. 
\begin{enumerate}
\item This is an item on the first level and has a run-in label This is an item on the first level and has a run-in label This is an item on the first level and has a run-in label This is an item on the first level and has a run-in label
\item This is an item on the first level and has a run-in label
  \begin{enumerate}
  \item This is an item on the second level and looks more familiar This is an item on the second level and looks more familiar This is an item on the second level and looks more familiar 
  \item This is an item on the second level and looks more familiar
  \end{enumerate}
\end{enumerate}
\end{document}