Writing Solution environment in Greek [duplicate]

Question

\documentclass{article}
\usepackage{amsthm,amssymb}
\author{Athanasios Paraskevopoulos}
\date{December 2022}
\title{ODE}
\newenvironment{solution}
  {\renewcommand\qedsymbol{$\blacksquare$}\begin{proof}[Solution]}
  {\end{proof}}

\begin{document}

\maketitle

 \begin{solution}[of some exercise]
     
    \end{solution}



\end{document}

I usually write my exercises with the above code. However, now I want to send the exercises they give us at the university written in LaTeX and I would like it to be in Greek. Can someone help me? Thanks in advance

Answer 1

Something like this? (is for pdfLaTeX and for Greek - English document with main language Greek). For LuaLaTeX or XeLaTeX is slightly different, let me know if you need it.

\documentclass{article}
\usepackage{amsthm,amssymb}
\usepackage[T1,LGR]{fontenc}
\usepackage[english,greek]{babel}
\author{Αθανάσιος Παρασκευόπουλος}
\date{Δεκέμβριος 2022}
\title{ODE}
\newenvironment{solution}
{\renewcommand\qedsymbol{$\blacksquare$}\begin{proof}[Λύση:]}
    {\end{proof}}

\begin{document}
    
    \maketitle
    
    \begin{solution}[Κάποιας άσκησης]
        
    \end{solution}

\end{document}