Delete empty page

Question

I have the next output:

And I want the text to start right after the box, even if is a chapter.

I have tried \let\cleardoublepage\clearpage command but doesn't work.

Here is the MWE:

\documentclass{tufte-book}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[left=2.50cm, right=2.50cm, top=3.00cm, bottom=2.00cm]{geometry}
\usepackage{xcolor}
\usepackage{tocloft} % added <<<<<<<<<<<<<<<<<<<<<<
\usepackage[mathscr]{euscript}
% matemáticas:
\usepackage{amsmath, amssymb} 
\usepackage{physics}
% idioma:
\usepackage[utf8]{inputenc}
\usepackage[spanish, es-tabla]{babel} % 'cuadro' es el título del caption de table por defecto siguiendo indicaciones de RAE; es-tabla lo cambia a 'tabla'
% gestión de párrafos (hace innecesario indicar el salto de línea con doble barra y elimina el indent de todos los párrafos):
\usepackage{parskip}
\usepackage{amssymb}
\usepackage[mathscr]{eucal} 
\usepackage{amsmath}
\usepackage[all]{xy}
\usepackage{lineno} 
\usepackage{epsfig} 
\usepackage{amscd}
\usepackage{mathrsfs}
\usepackage[thinc]{esdiff}
\usepackage[colorlinks=true,linkcolor=gray,citecolor=gray,urlcolor=gray,breaklinks]{hyperref} % changed <<<<<<
\usepackage[nameinlink]{cleveref}
%%******************************************************************** Changed 
\newcommand{\CourseName}{MT2223: Real analysis-I} % fill <<<<<<<<<<<<<<<<<<<<<<<
\newcommand{\CourseSemester}{Jan-May 2022}  % fill <<<<<<<<<<<<<<<<<<<<<<<
\newcommand{\CourseInstructor}{Praphulla Koushik}    % fill <<<<<<<<<<<<<<<<<<<<<<<
\newcommand{\listlecturename}{Clases \hfill {\footnotesize Página \par}} % title of the list <<<<<<<<<<<<<<<<
\newlistof[part]{lecture}{lec}{\listlecturename} % define list of lectures
\newcounter{lecnum}
\renewcommand{\thepage}{\thelecnum-\arabic{page}}
\renewcommand{\thesection}{\thelecnum.\arabic{section}}
\renewcommand{\theequation}{\thelecnum.\arabic{equation}}
\renewcommand{\thefigure}{\thelecnum.\arabic{figure}}
\renewcommand{\thetable}{\thelecnum.\arabic{table}}
\newcommand{\lecture}[2]{% changed <<<<<<<<<<<<<<<< use as  \lecture{number}{date}
    \pagestyle{myheadings}
    \newpage
    \setcounter{lecnum}{#1}
    \setcounter{page}{1}
    \refstepcounter{lecture}
    \addcontentsline{lec}{lecture}{Clase~#1:~#2}
    \noindent
    \fbox{%
    \begin{minipage}{\dimexpr\textwidth-2\fboxsep-2\fboxrule\relax}
        \begin{fullwidth}
        \centering\vspace{2mm}
        {\bfseries\CourseName \hfill \CourseSemester
         \vspace{4mm}\ 
         \Large \hfill  Clase #1  \hfill }
         \vspace{4mm}\

         {\normalfont Date: #2 \hfill  Profesor:~\CourseInstructor}
         \vspace{2mm}
         \end{fullwidth}
    \end{minipage}
}




\title{Tufte book}
\author{Álvaro Méndez Rodríguez de Tembleque}
\date{\today}
\begin{document}
\maketitle
\listoflecture 
\tableofcontents
\lecture{1}{Enero 30}
\chapter{Hola}
\end{document}

Answer 1

After:

1. removing all the clashing packages (I did not look why and where they clashed; you should have take care of that when adding the package); they are
   • geometry
   • eucal
   • xcolor
   • hyperref The thing compiled.

Then,

2. removing the extra spaces at the end of the line in the command \lecture
3. adding openany option to the class

Now the extra page is gone.

Notice that I do not advise using this as-is. Remove all packages and add them only when you need them, and find why someone clashes (probably tufte-book has already loaded most of them). For example, the last time epsfig was needed I think was around 1985. A rule of thumb is that you should exactly know why you load any package.

Minimally patched code here:

\documentclass[openany]{tufte-book}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
% \usepackage[left=2.50cm, right=2.50cm, top=3.00cm, bottom=2.00cm]{geometry}
% \usepackage{xcolor}
\usepackage{tocloft} % added <<<<<<<<<<<<<<<<<<<<<<
\usepackage[mathscr]{euscript}
% matemáticas:
\usepackage{amsmath, amssymb}
\usepackage{physics}
% idioma:
\usepackage[utf8]{inputenc}
\usepackage[spanish, es-tabla]{babel} % 'cuadro' es el título del caption de table por defecto siguiendo indicaciones de RAE; es-tabla lo cambia a 'tabla'
% gestión de párrafos (hace innecesario indicar el salto de línea con doble barra y elimina el indent de todos los párrafos):
\usepackage{parskip}
\usepackage{amssymb}
% \usepackage[mathscr]{eucal}
\usepackage{amsmath}
\usepackage[all]{xy}
\usepackage{lineno}
\usepackage{epsfig}
\usepackage{amscd}
\usepackage{mathrsfs}
\usepackage[thinc]{esdiff}
% \usepackage[colorlinks=true,linkcolor=gray,citecolor=gray,urlcolor=gray,breaklinks]{hyperref} % changed <<<<<<
\usepackage[nameinlink]{cleveref}
%%******************************************************************** Changed
\newcommand{\CourseName}{MT2223: Real analysis-I} % fill <<<<<<<<<<<<<<<<<<<<<<<
\newcommand{\CourseSemester}{Jan-May 2022}  % fill <<<<<<<<<<<<<<<<<<<<<<<
\newcommand{\CourseInstructor}{Praphulla Koushik}    % fill <<<<<<<<<<<<<<<<<<<<<<<
\newcommand{\listlecturename}{Clases \hfill {\footnotesize Página \par}} % title of the list <<<<<<<<<<<<<<<<
\newlistof[part]{lecture}{lec}{\listlecturename} % define list of lectures
\newcounter{lecnum}
\renewcommand{\thepage}{\thelecnum-\arabic{page}}
\renewcommand{\thesection}{\thelecnum.\arabic{section}}
\renewcommand{\theequation}{\thelecnum.\arabic{equation}}
\renewcommand{\thefigure}{\thelecnum.\arabic{figure}}
\renewcommand{\thetable}{\thelecnum.\arabic{table}}
\newcommand{\lecture}[2]{% changed <<<<<<<<<<<<<<<< use as  \lecture{number}{date}
    \pagestyle{myheadings}%
    \newpage
    \setcounter{lecnum}{#1}%
    \setcounter{page}{1}%
    \refstepcounter{lecture}%
    \addcontentsline{lec}{lecture}{Clase~#1:~#2}%
    \noindent
    \fbox{%
    \begin{minipage}{\dimexpr\textwidth-2\fboxsep-2\fboxrule\relax}
        \begin{fullwidth}%
        \centering\vspace{2mm}
        {\bfseries\CourseName \hfill \CourseSemester
         \vspace{4mm}\
         \Large \hfill  Clase #1  \hfill }
         \vspace{4mm}\
         {\normalfont Date: #2 \hfill  Profesor:~\CourseInstructor}
         \vspace{2mm}
         \end{fullwidth}%
    \end{minipage}%
    \par
}}
\title{Tufte book}
\author{Álvaro Méndez Rodríguez de Tembleque}
\date{\today}
\begin{document}
\maketitle
\listoflecture
\tableofcontents
\lecture{1}{Enero 30}
\chapter{Hola}
\end{document}