ThereasonLaTeXthinkstherearetoomany}'s here is that the opening curly brace is missing after the <tt>\\date</tt> control sequence and before the word December, so the closing curly brace is seen as one too many (which it is!).
Inthisexample,LaTeXiscomplainingthatithasnosuchcommand("control sequence")as<tt>\\dtae</tt>.Obviouslyit's been mistyped, but only a human can detect that fact: all LaTeX knows is that <tt>\\dtae</tt> is not a command it knows about: it'sundefined.
Acharacterthatcanonlybeusedinthemathematicswasinsertedinnormaltext.Ifyouintendedtousemathematicsmode,thenuse<tt>$...$</tt>or<tt>\\begin{math}...\\end{math}</tt>orusethe'quick math mode':<tt>\\ensuremath{...}</tt>.
Inthiserror,theclosingcurlybracehasbeenomittedfromthedate.It's the opposite of the error of too many }'s,anditresultsin<tt>\\maketitle</tt>tryingtoformatthetitlepagewhileLaTeXisstillexpectingmoretextforthedate!
Whenyouusethe<tt>\\usepackage</tt>commandtorequestLaTeXtouseacertainpackage,itwilllookforafilewiththespecifiednameandthefiletype<tt>.sty</tt>.Inthiscasetheuserhasmistypedthenameoftheparalistpackage,soit's easy to fix.