The following code works
\documentclass[12pt]{article}
\usepackage{enumerate} % line 2
%\usepackage{enumitem} % line 3
\begin{document}
\begin{enumerate}[(i)] % line 6
%\begin{enumerate}[noitemsep] % line 7
\item one
\item two
\end{enumerate}
\end{document}
and gives me something like
i. one
ii. two
But if I want to make the separation smaller, I would like to use enumitem package (following Wikibooks). However, I cannot use [(i)] when I use package enumitem. How can I get both of these features.

enumitemyou can uselabel=(\roman*)instead of(i). Aboutenumerate: https://tex.stackexchange.com/a/519982/134574. – Phelype Oleinik Jan 11 '20 at 02:21