\documentclass[tikz,border=5pt]{standalone}
\usepackage{tikz}
\usepackage{pgfplots}
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\usepackage{amsmath}
\begin{document}
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\begin{axis}[
title = {VGG-16},
xlabel={Epoch},
ylabel={Loss},
xmin=0, xmax=40,
ymin=0, ymax=6.5,
xtick={0, 10, 20, 30, 40, 50, 60},
ytick={0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5},
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\legend{Log Decay, Cosine Decay, No Scheduler, Step-Based Decay}
\end{axis}
\end{tikzpicture}
\end{document}