How do I add an indentation after creating a new line

You can use this trick \phantom{1.2)}.

\section*{Practice Problems}

1.2) A is a true statement. \\
\phantom{1.2)} B is a true statement. \newline
\phantom{1.2)} C is a false statement. \newline
\phantom{1.2)} D could be either false or true so it is not a statement.