How to make keywords of my algorithm appear in bold?

I want to write an algorithm in latex. But after compiling, it looks like that: As it looks, keywords like "Input", "Initialize","while", "end while" and "Output" don't appear in bold, I wonder if there is something wrong and how I can correct it.

    \begin{algorithm}
\caption{Title of the Algorithm}
\label{algo:ref}
\begin{algorithmic}[1]
\REQUIRE some words.  % this command shows "Input"
\ENSURE ~\\           % this command shows "Initialized"
some text goes here ... \\
\WHILE {\emph{not converged}}
\STATE ... \\  % line number at left side
\ENDWHILE
\RETURN this is the lat part.  % this command shows "Output"
\end{algorithmic}
\end{algorithm}


Besides, I used a template from Internet, and its introduction is as follows. Thanks for your help!

\documentclass[UTF8,a4paper,10pt]{ctexart}
\usepackage[left=2.50cm, right=2.50cm, top=2.50cm, bottom=2.50cm]{geometry} %页边距
\CTEXsetup[format={\Large\bfseries}]{section} %设置章标题居左

\setmainfont{STSong}   % 宋体

\usepackage{authblk}
\usepackage{amsmath, amsfonts, amssymb} % math equations, symbols
\usepackage[english]{babel}
\usepackage{color}      % color content
\usepackage{graphicx}   % import figures
\usepackage{bm}         % bold type for equations
\usepackage{multirow}
\usepackage{booktabs}
\usepackage{epstopdf}
\usepackage{epsfig}
\usepackage{algorithm}
\usepackage{algorithmic}
\renewcommand{\algorithmicrequire}{ \textbf{Input:}}     % use Input in the format of Algorithm
\renewcommand{\algorithmicensure}{ \textbf{Initialize:}} % use Initialize in the format of Algorithm
\renewcommand{\algorithmicreturn}{ \textbf{Output:}}     % use Output in the format of Algorithm
\renewcommand{\theequation}{\arabic{section}.\arabic{equation}}

\usepackage{fancyhdr} %设置页眉、页脚
\lfoot{}
\cfoot{}
\rfoot{}

\usepackage{hyperref} %bookmarks

\makeatletter
\makeatother

\title{\textbf{均匀设计方法综述}}
\author{ 陈海硕}
\affil{ 统计学院 }
\date{\today}

• Have a look at the listings package. – susis strolch Jul 15 at 4:04
• Hi and welcome. Please give a fully compilable code. – AndréC Jul 15 at 5:28

On the macOS 10.15, the warning says that the font TU/STSong(0)/b/n (font STSong bold) was unavailable (it doesn't exist) and that instead LaTeX used font TU/STSong(0)/m/n (font STSong).
Just delete the line \setmainfont{STSong} should resolve the issue or use another font that has both bold and italic shapes, e.g., Times New Roman.